About me

Dale R. Harshman, Ph.D.

email-@Physikon
email-@University of Notre Dame
email-@University of British Columbia
College of William and Mary webpage
ResearchGate webpage

Education

May 1986, University of British Columbia, Vancouver, BC
Ph.D. (Physics)
Thesis: The Interactions of Muonium with Silica Surfaces

June 1980, Western Washington University, Bellingham, WA
M.Sc. (Physics)

June 1978, Pacific Lutheran University, Tacoma, WA
B.Sc. (Physics)

Professional
Experience

Sep 2014 – Present, Department of Physics, College of William and Mary
Visiting Professor of Physics
Research – Principal Investigator

Aug 2014 – Present, University of Notre Dame
Consultant

Aug 1999 – Jul 2014, Department of Physics, University of Notre Dame
Visiting (Aug 1999 – Aug 2004) / Adjunct (Aug 2004 – Aug 2014) Professor of Physics
Research – Principal Investigator

Sep 1999 – Aug 2011, Department of Physics, Arizona State University
Visiting (Sep 1999 – Aug 2002) / Adjunct (Sep 2002 – Aug 2011) Professor of Physics
Research – Principal Investigator

Feb 1997 – Present, Physikon Research Corporation
Vice President (Feb 1997 – Dec 2017) / President (Jan 2018 – Present)
Director of Research / President and CEO

May 1988 – Feb 1997, AT&T/Lucent Bell Laboratories, Murray Hill, NJ
Member of Technical Staff (MTS)
Research – Principal Investigator more

Mar 1986 – May 1988, AT&T Bell Laboratories, Murray Hill, NJ
Postdoctoral Fellow (Pre-Member of Technical Staff – PMTS)
Research

Jan 1986 – Mar 1986, Department of Physics, University of British Columbia
Postdoctoral Fellow
Research

Aug 1980 – Jan 1986, Department of Physics, University of British Columbia
Doctoral Candidate / Research Associate
Research / Teaching Assistant

Sep 1978 – Jun 1980, Department of Physics, Western Washington University
Masters Candidate
Research / Teaching Assistant

Selected Research Highlights

Band-Gap Moderated Slow Positive Muon Beams – Dr. Harshman led the research group that discovered the first practical technique for producing a low-energy (<10 eV) positive muon beam. It was christened with the acronym, μSOL (muon separator on-line). The same 1986 paper reported the first observation of (< 10 eV) Mu^– (i.e., μ⁺e^–e^–) ions in vacuum. In 1987, Harshman and co-workers increased the slow muon production rate by a factor of 100 using solid rare-gas moderators, producing a usable flux of slow muons. [Physical Review Letters 56, 2850 (1986)] [Physical Review B 36, 8850 (1987)]. ‡The slow muon production technique developed by Harshman and coworkers was adopted by the Paul Sherrer Institut (PSI) for their slow positive muon beam facility (the μSR Yamazaki Prize for this work was awarded to PSI personnel who placed this technology on the end of a PSI surface muon channel).

Magnetic X-Ray Scattering in Holmium – By measuring the degree of linear polarization we identify the orbital and spin contributions to the x-ray magnetic scattering in holmium. When the incident x-ray energy is tuned through the L_m absorption edge, we observe a fiftyfold resonant enhancement of the magnetic signal, and resonant integer harmonics. The line shapes of the two linear components scattered parallel and perpendicular to the diffraction plane are distinct in energy with a 6-eV splitting. [Physical Review Letters 61, 1241 (1988)]. ‡This paper was the experimental work cited for the 2003 Arthur H. Compton Award, presented to its first and fourth authors, along with two others not directly involved with these experiments (Dr. Harshman declined first-authorship because of other obligations at the time). In addition to taking part in all aspects of this research, Dr. Harshman also commissioned and supervised the engineering of the novel x-ray spectrometer necessary for its success. During the experiment the acquisition computer failed; Dr. Harshman made the round trip from Cornell to Bell Labs to have it repaired.

High-Temperature Cuprate Superconductor Pairing State Symmetry – In 1987 using muon spin rotation (μ⁺SR) and measuring sintered powder samples of YBa₂Cu₃O_7–δ, Harshman and coworkers provided the first measurements of the magnetic penetration and proof that the bulk pairing state of the superconducting hole condensate was nodeless, consistent with s-wave pairing and strong coupling [Physical Review B 36, 2386 (1987)]. Harshman and co-workers were also the first to measure the 60 K (oxygen-ordered) phase of YBa₂Cu₃O_7–δ. This research was followed by studies of heavily twinned single crystals of the same material, confirming the s-wave character and providing the first measurement of the mass anisotropy; m_c ≥ 25 m_ab [Physical Review B 39, 851 (1989)]. In 1991, Harshman and co-workers presented μ⁺SR data on single-crystal Bi₂Sr₂CaCu₂O₈₊_δ showing a strongly temperature-dependent line shape, indicative of motional narrowing arising from fluxon depinning [Physical Review Letters 67, 3152 (1991)]. The fluxon lattice in earlier powder and heavily-twinned crystal samples of YBa₂Cu₃O_7–δ was strongly pinned, suppressing fluxon depinning. However, by the mid 90’s, the quality of YBa₂Cu₃O_7–δ crystals improved greatly, revealing a text-book example temperature-activated fluxon depinning. Unfortunately, some researchers misinterpreted the extrinsic effects of fluxon depinning as being evidence of d-wave pairing. To correct this misrepresentation, Harshman and co-workers conducted series of μ⁺SR experiments on a single-crystal of YBa₂Cu₃O_7–δ, measuring the second moment of the frequency distribution, σ(T0,H), as a function of both temperature and applied field. The strong (and non-monotonic) field dependence exhibited by σ(T→0,H),confirmed the presence of temperature-activated fluxon depinning. By applying a self-consistent analysis approach, and accounting for the effects of fluxon depinning, Harshman and co-workers showed that the underlying gap function of the superconducting hole condensate was nodeless, and best described by the two-fluid model. [Physical Review B 69, 174505 (2004)] [Physical Review B, 72, 146502 (2005)]. In 2011, Harshman and Fiory extended this analysis technique to YBa₂Cu₄O₈ and La_2-xSr_xCuO₄ [Journal of Physics: Condensed Matter 23, 315702 (2011)]. ‡This line of research has proven that the bulk high-T_C pairing symmetry of the hole condensate in the cuprates is nodeless, consistent with s-wave and strong coupling, and has shown how fluxon motion can significantly affect the μ⁺SR data, even for single-crystal YBa₂Cu₃O_7–δ, and how to account for it.

Oxygen Isotope Effect in High-T_C Materials – For high-T_C superconductors in which transition temperatures, T_C, are reduced by doping, the oxygen isotope effect (OIE) coefficient in T_C is shown to increase systematically with the pair-breaking rate and with the valence difference between the substituted and native ions. Moreover, the OIE in T_c tends to zero as one approaches optimum (or ideal) stoichiometry at which the quality of the superconducting condensate is maximized. In materials with isovalentsubstitutions, e.g., Sr for Ba or Zn for Cu in YBa₂Cu₃O_7–δ, the small OIE of the parent (unsubstituted) compound is magnified, owing to pair-breaking disorder. In materials with heterovalent substitutions, e.g., La or Pr for Ba, where carrier densities are necessarily changed, pair-breaking induces a much larger OIE. A seminal case is Pr-doped YBa₂Cu₃O_7–δ, where data were previously misinterpreted, owing to the false assumption that Pr substitutes only for Y. It is now clear, however, that the decrease in T_C observed with Pr doping actually arises from pair-breaking caused by Pr-on-Ba-site defects introduced during crystal growth. When PrBa₂Cu₃O_7–δ is grown correctly without such defects, T_C remains unchanged (as in the case of most other rare earth substitutions for Y). Invariance of T_C under a 60% rare-earth mass increase provides strong evidence against phononic pairing mechanisms. The fact that T_C drops when Pr substitutes for Ba, but not for Y, indicates that the superconducting hole condensate resides in the BaO layers, where pair-breaking degrades T_C and dramatically increases the OIE. Superconductive pairing modeled on Coulomb coupling between the hole (BaO) and the electron (CuO₂) layers is shown to resolve the serious shortcomings inherent in approaches based on electron-phonon interactions and is found to be generally applicable. Moreover, the OIE in the magnetic penetration depth in alloys is shown to be constant, with degradation of T_C up to 50%, and thus is unrelated to the OIE in T_C. [Physical Review B 77, 024523 (2008)] [Physical Review B 80, 136502 (2009)]. ‡This theoretical work corrects several earlier papers on the isotope effect in high-T_C compounds, concludes non-phononic mediation and casts the isotope effect into isovalent and heterovalent substitutional categories. Interpretations of differential OIE, combined with specific heat and thermal conductivity data indicate two interacting mobile carrier bands: one of holes and the other, electrons.

Coexistence of Holes and Electrons in High-T_C Compounds – Normal state resistivity and Hall effect are shown to be successfully modeled by a two-band model of holes and electrons that is applied self-consistently to (i) DC transport data reported for eight bulk-crystal and six oriented-film specimens of YBa₂Cu₃O_7–δ, and (ii) far-infrared Hall angle data reported for YBa₂Cu₃O_7–δ and Bi₂Sr₂CaCu₂O_8+δ. The electron band exhibits extremely strong scattering; the extrapolated DC residual resistivity of the electronic component is shown to be consistent with the previously observed excess thermal conductivity and excess electrodynamic conductivity at low temperature. Two-band hole-electron analysis of Hall angle data suggest that the electrons possess the greater effective mass. [Philosophical Magazine 91, 818 (2011)] [arXiv]. ‡Theoretical analysis of Hall effect data in high-T_C compounds showing the presence of two distinct carrier types of opposite sign. By applying a two-band model to the data from several DC and AC transport measurements, Dr. Harshman and co-workers were able to prove that mobile electrons coexist with the holes in the high-T_C compounds. The electrons were found to be heavier that the holes, possess 3D mobility (while the hole were generally confined to two dimensions) and exhibit strong scattering. This discovery suggested that the heavier electrons may play a role in mediating the pairing of lighter holes.

Theory of High-T_C Superconductivity: Transition Temperature – It is demonstrated that the transition temperature (T_C) of high-T_C superconductors is determined by their layered crystal structure, bond lengths, valency properties of the ions, and Coulomb coupling between electronic bands in adjacent, spatially separated layers. Analysis of 31 high-T_c materials (cuprates, ruthenates, rutheno-cuprates, iron pnictides, organics) yields the universal relationship for optimal compounds, k_BT_C0 = β/ℓζ, where ℓ is related to the mean spacing between interacting charges in the layers, ζ is the distance between interacting electronic layers, β is a universal constant and T_C0 is the optimal transition temperature (determined to within an uncertainty of ± 1.4 K by this relationship). Non-optimum compounds, in which sample degradation is evident, e.g. by broadened superconducting transitions and diminished Meissner fractions, typically exhibit reduced T_C< T_C0. It is shown that T_C0 may be obtained from an average of Coulomb interaction forces between the two layers. [Journal of Physics: Condensed Matter. 23, 295701 (2011)] [arXiv] [Corrigendum: J. Phys.: Condens. Matter 23 349501 (2011)]. Also listed in J. Phys.: Condens. Matter Highlights of 2011. ‡Seminal work on a theoretical model for high-T_C0 pairing based on Coulomb interactions between two nearest-neighbor charge layers. The fact that the universal constant β is equal to about twice the reduced electron Compton wavelength, and the equation for T_C0 in independent of band mass, suggests a central role for Compton scatting in high-T_C superconductivity, where pairing is accomplished via virtual photons.

Expansion of the High-T_C Interlayer/Interfacial Pairing Theory – Subsequent to the publication of the seminal work in 2011 (above), the interlayer Coulomb pairing model is shown to apply to other superconductor families; iron calcogenides [Journal of Physics: Condensed Matter 24, 135701 (2012)], the intercalated group-4-metal nitride halides [Physical Review B 90, 186501 (2014)] [Journal of Superconductivity and Novel Magnetism 28, 2967 (2015)] and (Ca_xLa_1–x)(Ba_1.75–xLa_0.25+x)Cu₃O_y (i.e., CLBLCO) [Physical Review B 86, 144533 (2012)]. For the charged compensated CLBLCO compound, the first accurate calculation of T_C for the related non-optimal materials is provided. Two Tl-based cuprates of the form Tl_1–x(Ba/Sr/La)₂CaO_5–δ [Journal of Physics and Chemistry of Solids 85, 106 (2015)] are also added to the growing list of compounds for which T_C is accurately calculated; a derivation of σ is introduced for the optimal Tl₂Ba₂Ca_η–1Cu_ηO_2η+2 (for η = 1, 2, 3) compounds, which exhibit a Tl oxidation state at or near +3, obtaining the fundamental value σ₀ = 0.228 previously established for YBa₂Cu₃O_6.92. Also reported is the marked enhancement in σ associated with Tl⁺¹ and analogous inner-layer cations relative to higher-valence cations. For a model proposition of σ = σ₀, the fractional Tl⁺¹ content of the mixed-valence compound, TlBa₂Ca₂Cu₃O_9±δ, is predicted to be 1/3 at optimization, in agreement with existing data. Gate-charged twisted bilayer graphene (TBG) has also been shown to be in compliance with the interlayer Coulomb pairing model [Journal of Superconductivity and Novel Magnetism (2019)]. ‡This work has unequivocally established the nature of the high-T_C pairing mechanism to be Coulombic, requiring interaction between two physically separated charge reservoirs. The theory is the only published predictive model for T_C in the high-T_C field.

Application of Coulomb Interlayer/Interfacial Pairing Theory to 3D Compounds – The applicability of the interfacial Coulombic pairing mechanism has been extended to the 3D macromolecular A₃C₆₀ superconducting family of compounds [Journal of Physics: Condensed Matter 29, 145602 (2017)] accurately predicts the optimal transition temperatures in A15 and fcc Cs₃C₆₀. Based upon the differing disorder between H3S and D3S [Superconductor Science and Technology 30, 045011 (2017)], the H-D isotope effect exponent is accurately determined in cubic H₃S, thereby setting significant limits on the electron-phonon coupling strength and opening the door to unconventional superconductivity. Subsequent application of the Coulomb interfacial mediation model to H₃S gives T_C0 = 198.5 ± 3.0 K is in excellent agreement with transition temperatures determined from resistivity (196 – 200 K onsets, 190 – 197 K midpoints), susceptibility (200 K onset), and critical magnetic fields (203.5 K by extrapolation). Analysis of mid-infrared reflectivity data also confirms the expected correlation between boson energy and ζ^–1 [Journal of Physics: Condensed Matter 29, 445702 (2017)]. ‡These results confirm that Coulombic mediation specifically requires physically separated charge reservoirs and is not determined by structural dimensionality.

Journal Publications (chronological order) more

Surface Interactions of Muonium in Oxide Powders at Low Temperatures, R. F. Kiefl, J. B. Warren, C. J. Oram, G. M. Marshall, J. H. Brewer, D. R. Harshman and C. W. Clawson, Physical Review B 26, 2432 (1982).

Giant Muon Knight Shifts in Antimony and Antimony Alloys, J. H. Brewer, D. R. Harshman, E. Koster, H. Schilling, D. Ll. Williams and M. G. Priestly, Solid State Communications 46, 863 (1983).

Positronium in SiO₂ Powder at Low Temperature, R. F. Kiefl and D. R. Harshman, Physics Letters 98A, 447 (1983).

Zero-Field Muon-Spin Relaxation in CuMn Spin-Glasses Compared with Neutron and Susceptibility Measurements, Y. J. Uemura, D. R. Harshman, M. Senba, E. J. Ansaldo and A. P. Murani, Physical Review B 30, 1606 (1984).

Diffusion and Trapping of Muonium on Silica Surfaces, D. R. Harshman, R. Keitel, M. Senba, R. F. Kiefl, E. J. Ansaldo and J. H. Brewer, Physics. Letters 104A, 472 (1984).

Muon Spin Relaxation in AuFe and CuMn Spin Glasses, Y. J. Uemura, T. Yamazaki, D. R. Harshman, M. Senba and E. J. Ansaldo, Physical Review B 31, 546 (1985).

Study of the Hybrid State of Y₉Co₇ (2 < T < 6 K) by Means of Zero Field Muon Spin Relaxation, E. J. Ansaldo, D. R. Noakes, J. H. Brewer, R. Keitel, D. R. Harshman, M. Senba, C. Y. Huang and B. V. B. Sarkissian, Solid State Communications 55, 193 (1985); [See also, µSR-Newsletter 30, 1661 (1984)].

MSR Measurement of the Reaction Rate of Muonium with a Supported Platinum Catalyst, R. F. Marzke, W. S. Glaunsinger, D. R. Harshman, E. J. Ansaldo, R. Keitel, M. Senba, D. R. Noakes, D. P. Spencer and J. H. Brewer, Chemical Physics Letters 120, 6 (1985).

Longitudinal-Field µ⁺ Spin Relaxation via Quadrupolar Level-Crossing Resonance in Cu at 20 K, S. R. Kreitzman, J. H. Brewer, D. R. Harshman, R. Keitel, D. Ll. Williams and E. J. Ansaldo, Physical Review Letters 56, 181 (1986); [See also, LF–µSR Quadrupolar Level Crossing Resonance in Copper at 20 K, S. R. Kreitzman, J. H. Brewer, D. R. Harshman, R. Keitel, D. Ll. Williams, K. M. Crowe and E. J. Ansaldo, µSR-Newsletter 30, 1675 (1984)]. ‡The experiments were conducted absent the first author.

Observation of Muon-Fluorine “Hydrogen Bonding” in Ionic Crystals, J. H. Brewer, S. R. Kreitzman, D. R. Noakes, E. J. Ansaldo, D. R. Harshman and R. Keitel, Physical Review B 33, 7813 (1986); [See also, µSR-Newsletter 31, 1747 (1985)]. ‡This phenomenon was originally discovered by D. R. Harshman and R. Keitel while conducting experiments on muon diffusion in NaF.

Anisotropic Muonium with Random Hyperfine Anisotropies: A New Static Relaxation Theory, R. E. Turner and D. R. Harshman, Physical Review B 34, 4467 (1986).

Observation of Low Energy µ⁺ Emission from Solid Surfaces, D. R. Harshman, J. B. Warren, J. L. Beveridge, K. R. Kendall, R. F. Kiefl, C. J. Oram, A. P. Mills, Jr., W. S. Crane, A. S. Rupaal and J. H. Turner, Physical Review Letters 56, 2850 (1986). ‡This work reported the first production of slow muons from solid surfaces (e.g., LiF) and presented the first published data of the production of Mu^– ions in vacuum.

Positive Muons in Sodium Fluoride: A Simple Spin System, D. R. Harshman and M. Celio, Physics Letters 118A, 351 (1986).

Electron, Muon and Nuclear Spin Dynamics in SmRh₄B₄ and ErRh₄B₄, D. R. Noakes, J. H. Brewer, D. R. Harshman, R. Keitel, E. J. Ansaldo, C. Y. Huang and S. E. Lambert, Physical Review B 35, 6597 (1987).

Antiferromagnetism and Oxygen Deficiency in Single-Crystal La₂CuO_4-δ, T. Freltoft, J. E. Fischer, G. Shirane, D. E. Moncton, S. K. Sinha, D. Vaknin, J. P. Remeika, A. S. Cooper and D. R. Harshman, Physical Review B 36, 826 (1987).

Temperature Dependence of the Magnetic Penetration Depth in the High-T_C Superconductor Ba₂YCu₃O_9-δ: Evidence for Conventional S-Wave Pairing, D. R. Harshman, G. Aeppli, E. J. Ansaldo, B. Batlogg, J. H. Brewer, J. F. Carolan, R. J. Cava, M. Celio. A. C. D. Chaklader, W. N. Hardy, S. R. Kreitzman, G. M. Luke, D. R. Noakes and M. Senba, Physical Review B 36, 2386 (1987).

Generation of Slow Positive Muons from Solid Rare-Gas Moderators, D. R. Harshman, A. P. Mills, Jr., J. L. Beveridge, K. R. Kendall, G. D. Morris, M. Senba, J. B. Warren, A. S. Rupaal and J. H. Turner, Physical Review B 36, 8850 (1987). ‡The slow muon production method pioneered here was adopted by the Paul Scherrer Institut (PSI) for their slow positive muon beam facility.

Temperature Dependence of the Positron Annihilation Lifetime in Single-Crystal YBa₂Cu₃O₇, D. R. Harshman, L. F. Schneemeyer, J. V. Waszczak, Y. C. Jean, M. J. Fluss, R. H. Howell and A. L. Wachs, Physical Review B 38, 848 (1988).

Freezing of Spin and Charge in La_2-xSr_xCuO₄, D. R. Harshman, G. Aeppli, G. P. Espinosa, A. S. Cooper, J. P. Remeika, E. J. Ansaldo, T. Riseman, D. Ll. Williams, D. R. Noakes, B. Ellman and T. F. Rosenbaum, Physical Review B 38, 852 (1988).

Antiferromagnetism and Superconductivity in Oxygen Deficient YBa₂Cu₃O_x, J. H. Brewer, E. J. Ansaldo, J. Carolan, A. C. D. Chaklader, W. N. Hardy, D. R. Harshman, M. Hayden, M. Ishikawa, N. Kaplan, R. Keitel, J. Kempton, R. F. Kiefl, W. J. Kossler, S. R. Kreitzman, A. Kulpa, Y. Kuno, G. M. Luke, H. Miyatake, K. Nagamine, Y. Nakazawa, N. Nishida, K. Nishiyama, S. Ohkuma, T. M. Riseman, G. Roehmer, P. Schleger, D. Shimada, C. E. Stronach, T. Takabatake, Y. J. Uemura, Y. Watanabe, D. Ll. Williams, T. Yamazaki and B. Yang, Physical Review Letters 60, 1073 (1988).

Electronic Structure of Studies La₂CuO₄, A. L. Wachs, P. E. A. Turchi, Y. C. Jean, R. H. Howell, K. H. Wetzler, M. J. Fluss, D. R. Harshman, J. P. Remeika, A. S. Cooper and R. M. Fleming, Physical Review B 38, 913 (1988).

Polarization and Resonance Properties of Magnetic X-Ray Scattering in Holmium, Doon Gibbs, D. R. Harshman, E. D. Isaacs, D. B. McWhan, D. Mills and C. Vettier, Physical Review Letters 61, 1241 (1988). ‡This paper was the experimental work cited for the 2003 Arthur H. Compton Prize, selectively awarded to its first and fourth authors, along with two theorists not involved with the experiment. In addition to taking part in all of the experiments, Dr. Harshman also designed, commissioned and supervised the building of the novel x-ray spectrometer necessary for its success. During the experiment the acquisition computer failed, and Dr. Harshman volunteered to make the round trip from Cornell to Bell Labs to have it repaired.

Comment on “Evidence for a Common High-Temperature Superconducting Effect in La_1.85Sr_0.15CuO₄ and YBa₂Cu₃O₇“, D. R. Harshman, L. F. Schneemeyer and J. V. Waszczak, Physical Review Letters 61, 2003 (1988).

Magnetic Penetration Depth in Single-Crystal YBa₂Cu₃O_7-δ, D. R. Harshman, L. F. Schneemeyer, J. V. Waszczak, G. Aeppli, R. J. Cava, B. Batlogg, L. W. Rupp, Jr., E. J. Ansaldo and D. Ll. Williams, Physical Review B 39, 851 (1989). ‡This paper reported on the first muon spin rotation measurement of the magnetic penetration depth in single-crystal YBa₂Cu₃O_7-δ. The mass anisotropy for YBa₂Cu₃O_7-δ (or any high-T_C compound) was measured for the first time using μ⁺SR.

Magnetic Penetration Depth of YBa₂Cu₃O₇, A. F. Hebard, A. T. Fiory and D. R. Harshman, Physical Review Letters 62, 2885 (1989).

Electronic Phase-Purity in La_2-xSr_xCuO_4-δ, D. R. Harshman, G. Aeppli, B. Batlogg, G. P. Espinosa, R. J. Cava, A. S. Cooper, L. W. Rupp, Jr., E. J. Ansaldo, and D. Ll. Williams,Physical Review Letters 63, 1187 (1989).

Magnetic Penetration Depth in the Organic Superconductor κ-[BEDT-TTF]₂Cu[NCS]₂, D. R. Harshman, R. N. Kleiman, R. C. Haddon, S. V. Chichester-Hicks, M. L. Kaplan, L. W. Rupp, Jr., D. Ll. Williams and D. B. Mitzi, Physical. Review Letters 64, 1293 (1990).

Anisotropic Temperature Dependence of the Magnetic Penetration Depth in Superconducting UPt₃, C. Broholm, G. Aeppli, R. N. Kleiman, D. R. Harshman, D. J. Bishop, E. Bucher, D. Ll. Williams, E. J. Ansaldo and R. H. Heffner, Physical Review Letters 65, 2062 (1990).

Polarization and Resonance Studies of X-Ray Magnetic Scattering in Holmium, Doon Gibbs, G. Grubel, D. R. Harshman, E. D. Isaacs, D. B. McWhan, D. Mills and C. Vettier, Physical Review B 43, 5663 (1991).

Local Magnetic Fields in the Pinned Vortex State: Effect on the µ⁺-Spin Rotation Lineshape, D. R. Harshman, A. T. Fiory and R. J. Cava, Phys. Rev. Lett. 66, 3313 (1991). Erratum: Physical Review Letters 67, 2748 (1991).

Pair Momentum Distribution in Bi₂Sr₂CaCu₂O_8+δ Measured by Positron 2D-ACAR: Existence and Nature of the Fermi Surface, L. P. Chan, D. R. Harshman, K. G. Lynn, S. Massidda and D. B. Mitzi, Physical Review Letters 67, 1350 (1991).

Magnetic Penetration Depth and Flux-Dynamics in Single-Crystal Bi₂Sr₂CaCu₂O_8+δ, D. R. Harshman, R. N. Kleiman, M. Inui, G. P. Espinosa, D. B. Mitzi, A. Kapitulnik, T. Pfiz and D. Ll. Williams, Physical Review Letters 67, 3152 (1991).

Concerning the Nature of High-T_C Superconductivity: Survey of Experimental Properties and Implications for Interlayer Coupling, D. R. Harshman and A. P. Mills, Jr., Physical Review B 45, 10684 (1992).

Can Positron 2D-ACAR Resolve the Electronic Structure of High-T_CSuperconductors?, L. P. Chan, D. R. Harshman and K. G. Lynn, Modern Physics Letters B 6, 617 (1992).

Longitudinal Correlation Length of Vortices in Anisotropic Superconductors, D. R. Harshman, E. H. Brandt, A. T. Fiory, M. Inui, D. B. Mitzi, L. F. Schneemeyer and J. V. Waszczak, Physical Review B 47, 2905 (1993).

Muon Spin Relaxation Experiments and Magnetic Flux Lines in the Mixed State High Temperature Superconductors, M. Inui and D. R. Harshman, Physical Review B 47, 12205 (1993).

Working Group on Condensed Matter Physics, J. Axe, C. Broholm, D. R. Harshman, S. Hayden, H. Mook, S. Nadler, R. Osborn and P. Sokol, in Proceedings of the Workshop on Technology and Scientific Opportunities at a 1 MW Pulsed Spallation Neutron Source, Argonne National Laboratory, Argonne, Illinois, 13 – 16 May 1993 (published in February 1994).

Comment on “Universal Trends in Extreme Type-II Superconductors”, D. R. Harshman and A. T. Fiory, Physical Review Letters 72, 1132 (1994).

Muon Spin Rotation in Overdoped Tl₂Ba₂CuO_6+δ, D. R. Harshman and A. T. Fiory, Physical Review Letters 72, 2501 (1994).

Magnetic Penetration Depth and Fluxon-Line Dynamics in the Organic Superconductor κ-[BEDT-TTF]₂Cu[NCS]₂, D. R. Harshman, A. T. Fiory, R. C. Haddon, M. L. Kaplan, T. Pfiz, E. Koster, I. Shinkoda and D. Ll. Williams, Physical Review B 49, 12990 (1994).

Vacancy Defects in Photoexcited GaAs Studied by Positron Two-Dimensional Angular Correlation of Annihilation Radiation, J. P. Peng, M. T. Umlor, K. G. Lynn, D. J. Keeble and D. R. Harshman, Physical Review B 50, 11247 (1994).

Two Dimensional Angular Correlation of Annihilation Radiation Study of κ-[BEDT-TTF]₂Cu[NCS]₂, L. P. Chan, K. G. Lynn, D. R. Harshman and R. C. Haddon, Physical Review B 50, 10393 (1994).

Study of the SiO₂/Si Interface Using Variable Energy Positron Two-Dimensional Angular Correlation of Annihilation Radiation, J. P. Peng, K. G. Lynn, P. Asoka-Kumar, D. P. Becker and D. R. Harshman, Physical Review Letters 76, 2157 (1996).

Vortex Lattice Disorder in Untwinned Single Crystal YBa₂Cu₃O_7-δ, W. J. Kossler, A. D. de Goonewardene, A. J. Greer, D. Ll. Williams, E. Koster, D. R. Harshman, J. Z. Liu and R. N. Shelton, Physical Review B 56, 2376 (1997).

Transparency of the ab Planes of Bi₂Sr₂CaCu₂O_x to Magnetic Fields, W. J. Kossler, Y. Dai, K. G. Petzinger, A. J. Greer, D. Ll. Williams, E. Koster, D. R. Harshman and D. B. Mitzi, Physical Review Letters 80, 592 (1998).

Magnetism and Superconductivity in Sr₂YRu_1-uCu_uO₆ and Magnetism in Ba₂GdRu_1-uCu_uO₆, H. A. Blackstead, John D. Dow, D. R. Harshman, M. J. DeMarco, M. K. Wu, D. Y. Chen, F. Z. Chien, D. B. Pulling, W. J. Kossler, A. J. Greer, C. E. Stronach, E. Koster and B. Hitti, European Physical Journal B 15, 649 (2000).

Magnetically Ordered Cu and Ru in Ba₂GdRu_1-uCu_uO₆ and in Sr₂YRu_1-uCu_uO₆, Howard A. Blackstead, John D. Dow, Dale R. Harshman, W. B. Yelon, M. X. Chen, M. K. Wu, D. Y. Chen, F. Z. Chien and D. B. Pulling,Physical Review B 63, 214412 (2001).

Magnetic Susceptibility and Resonance Studies of Ordering in Ba₂GdRu_1-uCu_uO₆, Howard A. Blackstead, John D. Dow, Dale R. Harshman, D. B. Pulling, M. K. Wu, D. Y. Chen and F. Z. Chien, Solid State Communications 118, 355 (2001).

Explanation of High-Temperature Superconductivity Without Cuprate Planes, John D. Dow and Dale R. Harshman, Philosophical Magazine B 82, 1055 (2002).

Spin-Glass Behavior, Spin Fluctuations and Superconductivity in Sr₂Y(Ru_1-uCu_u)O₆, Dale. R. Harshman, W. J. Kossler, A. J. Greer, D. R. Noakes, C. E. Stronach, E. Koster, M. K. Wu, F. Z. Chien, J. P. Franck, I. Isaac and John D. Dow, Physical Review B 67, 054509 (2003).

Muon Spin Rotation in GdSr₂Cu₂RuO₈: Implications, Dale R. Harshman, John D. Dow, W. J. Kossler, D. R. Noakes, C. E. Stronach, A. J. Greer, E. Koster, Z. F. Ren and D. Z. Wang, Philosophical Magazine 83, 3055 (2003).

Muon Spin Rotation Study of the (TMTSF)₂ClO₄ System, A. J. Greer, D. R. Harshman, W. J. Kossler, A. Goonewardene, D. Ll. Williams, E. Koster, W. Kang, R. N. Kleiman and R. C. Haddon, Physica C 400 (issues 1-2), 59 (2003).

Nodeless Pairing-State Gap Function in Single-Crystal YBa₂Cu₃O₇, Dale R. Harshman, W. J. Kossler, X. Wan, A. T. Fiory, A. J. Greer, D. R. Noakes, C. E. Stronach, E. Koster, and John D. Dow, Physical Review B 69, 174505 (2004). ‡Experiment confirming the nodeless character of the bulk high-T_C hole condensate.

Implications of Gd Destroying High-Temperature Superconductivity, John D. Dow and Dale R. Harshman, Modern Physics Letters B 19, 401 (2005).

Reply to “Comment on ‘Nodeless Pairing State in Single-Crystal YBa₂Cu₃O₇‘”, Dale R. Harshman, W. J. Kossler, X. Wan, Anthony T. Fiory, A. J. Greer, D. R. Noakes, C. E. Stronach, E. Koster and John D. Dow, Physical Review B, 72, 146502 (2005).

Electron-Hole Superlattices in GaAs/Al_xGa_1-xAs Multiple Quantum Wells, K. P. Walsh, A. T. Fiory, N. M. Ravindra, Dale R. Harshman and John D. Dow, Philosophical Magazine 86, 3581 (2006).

Isotope Effect in High-T_C Superconductors, Dale R. Harshman, John D. Dow and Anthony T. Fiory,Physical Review B 77, 024523 (2008). ‡Theoretical work correcting several earlier papers on the isotope effect in high-T_C compounds, concluding non-phononic mediation and casting the isotope effect into isovalent and heterovalent substitutional categories. Interpretations of differential OIE, combined with specific heat and and thermal conductivity data indicate two interacting mobile carrier bands: one of holes and the other, electrons.

Correct Nature of High-Temperature Superconductivity, John D. Dow and Dale R. Harshman, Journal of Superconductivity and Novel Magnetism 22, 29 (2009).

Reply to “Comment on ‘Isotope Effect in High-T_C Superconductors’”, Dale R. Harshman, John D. Dow and Anthony T. Fiory, Physical Review B 80, 136502 (2009).

Coexisting Holes and Electrons in High-T_C Materials: Implications from normal state transport,Dale R. Harshman, John D. Dow and Anthony T. Fiory, Philosophical Magazine 91, 818 (2011). ‡Theoretical analysis of Hall effect data in high-T_C compounds showing the presence of two distinct carrier types of opposite sign. By applying a two-band model to the data from several DC and AC transport measurements, it was conclusively shown that mobile electrons coexist with the holes in the high-T_C compounds. The electrons were found to be heavier that the holes, possess 3D mobility (while the hole were generally confined to two dimensions) and exhibit strong scattering. This discovery suggested that the heavier electrons likely play a role in mediating the pairing of lighter holes.

Theory of High-T_C Superconductivity: Transition Temperature, Dale R. Harshman, Anthony T. Fiory and John D. Dow, Journal of Physics: Condensed Matter 23, 295701 (2011); News Article; Corrigendum:Journal of Physics: Condensed Matter 23, 349501 (2011). Also listed in J. Phys.: Condens. Matter Highlights of 2011. ‡Seminal work on a theoretical model for high-T_C pairing based on Coulomb interactions between two nearest-neighbor charge layers. The fact that the universal constant β is equal to about twice the reduced electron Compton wavelength, and the equation for T_C0 in independent of band mass, suggests a central role for Compton scatting in high-T_C superconductivity, where pairing is accomplished via virtual photons.

Concerning the Superconducting Gap Symmetry in YBa₂Cu₃O_7–δ, YBa₂Cu₄O₈, and La_2-xSr_xCuO₄Determined from Muon Spin Rotation in Mixed States of Crystals and Powders, Dale R. Harshman and Anthony T. Fiory, Journal of Physics: Condensed Matter 23, 315702 (2011). ‡Theoretical treatment of μ⁺SR data showing that for studies of the mixed state, there is clear evidence supporting a nodeless gap function, consistent with strong-coupled s-wave pairing. These results are compared to results obtained using other other experimental techniques, both static and dynamic, in the mixed and Meissner states. These results corrected the misrepresentation regarding the pairing state symmetry in the cuprate superconductors.

High-T_C Superconductivity in Ultra-Thin Crystals: Implications for Microscopic Theory, D. R. Harshman and A. T. Fiory, Emerging Materials Research 1, 4 (2012).

The Superconducting Transition Temperatures of Fe_1+xSe_1–y, Fe_1+xSe_1–yTe_yand (K/Rb/Cs)_zFe_2–xSe₂, D. R. Harshman and A. T. Fiory, Journal of Physics: Condensed Matter 24, 135701 (2012). ‡Theoretical treatment showing that the Se-based iron chalcogenide superconductors are high-T_C in nature, whose optimal transition temperatures T_C0 are given by our interlayer Coulombic-coupling mechanism; thus increasing to 36 known compliant compounds from six different superconducting families.

Charge Compensation and Optimal Stoichiometry in (Ca_xLa_1–x)(Ba_1.75–xLa_0.25+x)Cu₃O_y, D. R. Harshman and Anthony T. Fiory, Physical Review B 86, 144533 (2012). ‡Theoretical consideration of the title compound (abbreviated CLBLCO) showing the following: (1) Superconducting CLBLCO has only one optimal stoichiometry, and resolves the conflicting experimental interpretations on CLBLCO; (2) T_C is non-proportional to n/m*; (3) By scaling the Ba-ion content with respect to YBa₂Cu₃O_6.92, T_C0 is calculated to within a few K of experiment; (4) X-ray absorption results place most of the superconducting condensate outside the cuprate planes; chemical strain considered by the discovering group is shown to be a minor perturbation; and (5) Explains that superconductivity in CLBLCO is nonsymbiotic with magnetic phenomena observed in non-superconducting underdoped compositions.

Comment on “Superconductivity in Electron-Doped Layered TiNCl with Variable Interlayer Coupling”, Dale R. Harshman and Anthony T. Fiory, Physical Review B 90, 186501 (2014). ‡The interlayer Coulombic pairing model is shown to apply to the intercalated/co-intercalated TiNCl compounds, which exhibit remote Coulomb scattering (RCS). The mediating interaction occurs between the Cl anion (superconducting) layer and the cations of the intercalation (mediating) layer. Optimization is shown to occur with decreasing RCS pair breaking, i.e., as the distance between the two interacting layers is increased above ~7 Å.

The Interaction Charge Density in Thallium-Based High-T_C Cuprates: Roles of cation oxidation state and electronegativity, Dale R. Harshman and Anthony T. Fiory, Journal of Physics and Chemistry of Solids 85, 106 (2015).

Modeling Intercalated Group-4-Metal Nitride Halide Superconductivity with Interlayer Coulomb Coupling, Dale R. Harshman and Anthony T. Fiory, Journal of Superconductivity and Novel Magnetism 28, 2967 (2015).

High-T_C Superconductivity in Cs₃C₆₀ Compounds Governed by Local Cs-C₆₀ Coulomb Interactions, Dale R. Harshman and Anthony T. Fiory, Journal of Physics: Condensed Matter 29, 145602 (2017). ‡This study accurately predicts the optimal transition temperatures in A15 and fcc Cs₃C₆₀ and represents the successful application of the Coulombic (interlayer/interfacial) pairing theory to a three-dimensional system.

On the Isotope Effect in Compressed H₃S and D₃S, Dale R. Harshman and Anthony T. Fiory, Superconductor Science and Technology 30, 045011 (2017). ‡The H-D isotope effect exponent is accurately determined in H₃S based upon the differing disorder between H₃S and D₃S, thereby setting significant limits on the electron-phonon coupling strength.

Compressed H₃S: Inter-Sublattice Coulomb Coupling in a High-T_C Superconductor, Dale R. Harshman and Anthony T. Fiory, Journal of Physics: Condensed Matter 29, 445702 (2017). ‡Our findings regarding the true magnitude of the H-D isotope effect exponent suggests that the superconductivity in H₃S is non-phononic in origin. This work represents the first application of the Coulomb Interfacial pairing model to a structurally 3D covalently-bonded compound.

High-T_C Superconductivity Originating from Interlayer Coulomb Coupling in Gate-Charged Twisted Bilayer Graphene Moiré Superlattices, Dale R. Harshman and Anthony T. Fiory, Journal of Superconductivity and Novel Magnetism (2019). ‡Given the presence of interlayer excitons, binary Twisted Bilayer Graphene (TBG) devices have proven to be an ideal test case for our Interlayer Coulomb Pairing Model.

Conference Publications more

Muonium in Al₂O₃ Powder at Low Temperatures, R. F. Kiefl, J. B. Warren, C. J. Oram, J. H. Brewer and D. R. Harshman, in Positron Annihilation, edited by P. G. Coleman, S. C. Sharma and L. M. Diana, p. 693 (North-Holland Publishing Company, 1983).

Magnetic Susceptibility, Proton NMR and Muon Spin Rotation (µSR) Studies of an Unsupported Platinum Catalyst with Adsorbed H and O, R. F. Marzke, W. S. Glaunsinger, K. B. Rawlings, P. Van Rheenen, M. McKelvy, J. H. Brewer, D. R. Harshmanand R. F. Kiefl, in Electronic Structure and Properties of Hydrogen in Metals, edited by P. Jena and C. B. Satterthwaite (Plenum Publishing Corporation, 1983).

Dynamical Behavior of Muonium on Silica Surfaces, D. R. Harshman, R. Keitel, M. Senba, E. J. Ansaldo and J. H. Brewer, Hyperfine Interactions 17-19, 557 (1984).

Hyperfine Splitting of Muonium in SiO₂ Powder, R. F. Kiefl, B. D. Patterson, E. Holzschuh, W. Odermatt and D. R. Harshman, Hyperfine Interactions 17-19, 563 (1984).

Zero-Field µSR in a Spin Glass CuMn (1.1 at. %): Precise Measurement of Static and Dynamic Effects Below T_g, Y. J. Uemura, T. Yamazaki, D. R. Harshman, M. Senba, J. H. Brewer, E. J. Ansaldo and R. Keitel, Hyperfine Interactions 17-19, 453 (1984).

µ⁺SR Study of Some Magnetic Superconductors, C. Y. Huang, E. J. Ansaldo, J. H. Brewer, D. R. Harshman, K. M, Crowe, S. S. Rosenblum, C. W. Clawson, Z. Fisk, S. Lambert, M. S. Torikachvili and M. B. Maple, Hyperfine Interactions 17-19, 509 (1984).

Positive Muon Knight Shift in Graphite and Grafoil, F. N. Gygax, A. Hintermann, A. Schenck, W. Studer, A. J. van der Wal, J. H. Brewer and D. R. Harshman, Hyperfine Interactions 17-19, 383 (1984).

Positive Muons in Antimony Bismuth Alloys, F. N. Gygax, A. Hintermann, A. Schenck, W. Studer, A. J. van der Wal, J. H. Brewer, D. R. Harshman, E. Koster, H. Schilling, D. Ll. Williams and M. G. Priestly, Hyperfine Interactions 17-19, 387 (1984).

Muon Spin Relaxation in ErRh₄B₄, D. R. Noakes, E. J. Ansaldo, J. H. Brewer, D. R. Harshman, C. Y. Huang, M. S. Torikachvili, S. E. Lambert and M. B. Maple, Journal of Applied Physics 57, 3197 (1985).

Production of Muonium in Vacuum from Silica Powders, G. M. Marshall, G. A. Beer, T. Bowen, Z. Gelbart, P. G. Halverson, D. R. Harshman, K. R. Kendall, A. R Kunselman, G. R. Mason, A. Olin and J. B. Warren, in Proceedings of the Los Alamos Workshop on Fundamental Muon Physics: Atoms, Nuclei and Particles, Los Alamos, New Mexico, USA, 20 – 22 January 1986.

The Relaxation Rate of Muonium as a Function of Temperature and Loading in Silica-supported Platinum Catalysts, R. F. Marzke, D. R. Harshman, E. J. Ansaldo, R. Keitel, M. Senba, D. R. Noakes and J. H. Brewer, Ultramicroscopy 20, 161 (1986).

Muon/Muonium Surface Interactions, D. R. Harshman, Invited Paper, in Proceedings of the µSR-86 Conference, Uppsala, Sweden, 23 – 27 June 1986, Hyperfine Interactions 32, 847 (1986).

Muonium in Bulk Fused Quartz: Test Case for RAHD Relaxation Theory, D. R. Harshman, R. E. Turner, J. H. Brewer and D. P. Spencer, in Proceedings of the µSR-86 Conference, Uppsala, Sweden, 23 – 27 June 1986, Hyperfine Interactions 32, 527 (1986).

Positive Muons in Single Crystal Sodium Fluoride: A Simple Spin System, D. R. Harshman and M. Celio, in Proceedings of the µSR-86 Conference, Uppsala, Sweden, 23 – 27 June 1986, Hyperfine Interactions 32, 683 (1986).

Observation of Muon Level-Crossing Resonance in Antiferromagnetic MnF₂, G. M. Luke, R. F. Kiefl, S. R. Kreitzman, J. H. Brewer, R. Keitel, D. R. Noakes, Y. J. Uemura, D. R. Harshman and V. Jaccarino, in Proceedings of µSR-86 Conference, Uppsala, Sweden, 23 – 27 June 1986, Hyperfine Interactions 31, 29 (1986).

Determination of Very Slow µ⁺ Hop Rates in Cu by LF-µSR, J. H. Brewer, M. Celio, D. R. Harshman, R. Keitel, S. R. Kreitzman, G. M. Luke, D. R. Noakes, R. E. Turner, E. J. Ansaldo, C. W. Clawson, K. M. Crowe, S. Kohn, S. R. Rosenblum, J. Smith and C. Y. Huang, in Proceedings of the μSR-86 Conference, Uppsala, Sweden, 23 – 27 June 1986, Hyperfine Interactions 31, 191 (1986).

µSR Studies on Pure MnF₂ and Site-Diluted (Mn_0.5Zn_0.5)F₂, Y. J. Uemura, R. Keitel, M. Senba, R. F. Kiefl, S. R. Kreitzman, D. R. Noakes, J. H. Brewer, D. R. Harshman, E. J. Ansaldo, K. M. Crowe and V. Jaccarino, inProceedings of the µSR-86 Conference, Uppsala, Sweden, 23 – 27 June 1986, Hyperfine Interactions 31, 313 (1986).

µ⁺ Knight Shifts and Trapping in Dilute SbSn Alloys, J. H. Brewer, D. R. Harshman, E. Koster, S. R. Kreitzman, D. R. Noakes, M. Senba and D. Ll. Williams, in Proceedings of the µSR-86 Conference, Uppsala, Sweden, 23 – 27 June 1986, Hyperfine Interactions 31, 433 (1986).

Thermal Hopping of µ⁺ Between “FµF” Centres in NaF, J. H. Brewer, D. R. Harshman, R. Keitel, S. R. Kreitzman, G. M. Luke, D. R. Noakes, R. E. Turner and E. J. Ansaldo, in Proceedings of the µSR-86 Conference, Uppsala, Sweden, 23 – 27 June 1986, Hyperfine Interactions 32, 677 (1986).

Muonium Reaction with Ethylene on Powder Surfaces, R. Keitel, M. Senba and D. R. Harshman, inProceedings of the µSR-86 Conference, Uppsala, Sweden, 23 – 27 June 1986, Hyperfine Interactions 32, 865 (1986).

Slow Muon Physics, D. R. Harshman, Invited Paper, in Proceedings of the NATO Advanced Research Workshop on Atomic Physics with Positrons, London, United Kingdom, 15 – 18 July 1987.

Magnetic Correlations in La₂NiO_4+δ and La_2-xSr_xCuO₄, G. Aeppli, D. R. Harshman, D. Buttrey, E. J. Ansaldo, G. P. Espinosa, A. S. Cooper, J. P. Remeika, T. Freltoft, T. M. Riseman, D. R. Noakes, B. Ellman, T. F. Rosenbaum and D. Ll. Williams, Physica C 153-155, 1111 (1988).

Temperature Dependence of the Magnetic Penetration Depth in YBa₂Cu₃O₇Measured by Muon Spin Rotation, R. F. Kiefl, T. M. Riseman, G. Aeppli, E. J. Ansaldo, J. F. Carolan, R. J. Cava, W. N. Hardy, D. R. Harshman, N. Kaplan, J. R. Kempton, S. R. Kreitzman, G. M. Luke, B. X. Yang, D. Ll. Williams, Physica C 153-155, 757 (1988).

Electronic Structure Investigations of High-T_C Materials by Positron Annihilation Spectroscopy: Theory and Experiment, A. L. Wachs, P. E. A. Turchi, Y. C. Jean, K. H. Wetzler, R. H. Howell, D. R. Harshman, J. P. Remeika, A. S. Cooper, R. M. Fleming and M. J. Fluss, in Proceedings of the MRS Meeting, Reno, Nevada, USA, 5 – 8 April 1988.

Polarization Analysis of X-Ray Magnetic Scattering, Doon Gibbs, M. Blume, D. R. Harshman and D. B. McWhan, Invited Paper, in Proceedings of the Third International Conference on Synchrotron Radiation Instrumentation, Tsukuba, Japan, 4 September 1988, Reviews of Scientific Instruments 60, 1655 (1989).

Magnetic Penetration Depth of Bi-Sr-Ca-Cu-O, E. J. Ansaldo, B. Batlogg, R. J. Cava, D. R. Harshman, L. W. Rupp, Jr., T. M. Riseman and D. Ll. Williams, Physica C 162-164, 259 (1989).

Superconductivity of UPt₃ Studied by µ⁺SR and Neutron Scattering, C. Broholm, R. N. Kleiman, G. Aeppli, D. R. Harshman, D. J. Bishop, E. Bucher, D. Ll. Williams, R. H. Heffner, and E. J. Ansaldo, in Proceedings of MMM Conference, San Diego, California, USA, 29 Oct. – 1 Nov. 1990, Journal of Applied Physics 69, 5491 (1991).

Application of Muon Spin Relaxation Experiment to the Mixed-State Superconductors, M. Inui and D. R. Harshman, in Proceedings of the Conference on Physical Phenomena at High Magnetic Fields, Tallahassee, Florida, USA, 15 – 18 May 1991.

Application of Muon Spin Relaxation Experiment to the Vortex Dynamics of High-T_C Superconductors, M. Inui and D. R. Harshman, in Proceedings of the Int’l. Conf. of the Materials and Mechanisms of Superconductivity – High Temperature Superconductors III, Kanazawa, Japan, 22 – 26 July 1991.

Muon Spin Relaxation Studies of the Layered Copper Oxides, G. Aeppli and D. R. Harshman, in Proceedings of the Univ. of Miami Workshop on: Electronic Structure and Mechanisms for High Temperature Superconductivity, Miami, Florida, USA, 3 – 9 January 1991.

Evidence for a Fermi Surface in Bi₂Sr₂CaCu₂O_8+δ Measured by Positron 2D-ACAR, L. P. Chan, D. R. Harshman, K. G. Lynn, S. Massidda and D. B. Mitzi, Invited Paper, in Proceedings of the Conference on the Fermiology of High-T_C Superconductors, Argonne National Laboratory, Argonne, Illinois, 25-27 March 1991,Journal of Physics and Chemistry of Solids 52, 1557 (1991).

Slow Muon Physics: Applications to Problems in Superconductivity, D. R. Harshman, Invited Paper, in Proceedings of the International Workshop on Low Energy Muon Science (LEMS’93), Sante Fe, New Mexico, USA, 4 – 8 April 1993, M. Leon, Ed.

High-T_C Superconductivity: Applications of µ⁺SR and Slow µ⁺ Beams, D. R. Harshman, Invited Paper, in Proceedings of the International School of Physics, Enrico Fermi Course on Positron Spectroscopy of Solids, Varenna, Italy, 6 – 16 July 1993.

Muon Spin Rotation in Sr₂YRu_1-uCu_uO₆, D. R. Harshman, H. A. Blackstead, W. J. Kossler, A. J. Greer, C. E. Stronach, E. Koster, B. Hitti, M. K. Wu, D. Y. Chen, F. Z. Chien and J. D. Dow, Invited Paper, in Proceedings of the Second Annual Conference on New Theories, Discoveries and Applications of Superconductors and Related Materials (New3SC-2), Las Vegas, Nevada, USA, 31 May – 3 June 1999, International Journal of Modern Physics B 13, 3670 (1999).

Location of the Superconducting Hole Condensate in Sr₂YRu_1-uCu_uO₆, D. R. Harshman, W. J. Kossler, A. J. Greer, C. E. Stronach, E. Koster, B. Hitti, M. K. Wu, D. Y. Chen, F. Z. Chien, H. A. Blackstead and J. D. Dow, in Proceedings of the 8^th International Conference on Muon Spin Rotation, Relaxation and Resonance (µSR-99), Les Diablerets, Switzerland, 30 August – 3 September 1999, Physica B 289-290, 360 (2000).

Location and Properties of the Superconducting Hole-Condensate in Sr₂YRu_1-uCu_uO₆, Howard A. Blackstead, John D. Dow, Dale R. Harshman, David B. Pulling, W. J. Kossler, A. J. Greer, C. E. Stronach, E. Koster, B. Hitti, M. K. Wu, D. Y. Chen and F. Z. Chien, in Proceedings of the 6th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors (M2S-HTSC-VI), Houston, Texas, 20-25 February 2000, Physica C 341-348 (1-4), 163-164 (2000).

Eu_2-zCe_zSr₂Cu₂RuO₁₀ Superconducts in its SrO layers, not in the Cuprate Planes, Howard A. Blackstead, John D. Dow, Dale R. Harshman, Israel Felner, David B. Pulling, W. J. Kossler, A. J. Greer, C. E. Stronach, E. Koster and B. Hitti, in Proceedings of the 6th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors (M2S-HTSC-VI), Houston, Texas, 20-25 February 2000, Physica C 341-348, 165-166 (2000).

Magnetic Resonance and Surface Resistance of Ba₂GdRu_1-uCu_uO₆, Howard A. Blackstead, John D. Dow, Dale R. Harshman, David B. Pulling, M. K. Wu, D. Y. Chen and F. Z. Chien, in Proceedings of the 6th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors (M2S-HTSC-VI), Houston, Texas, 20-25 February 2000, Physica C 341-348 (1-4), 571-572 (2000).

Sr₂YRu_1-uCu_uO₆: Evidence for SrO-Layer Superconductivity, Howard A. Blackstead, John D. Dow andDale R. Harshman, in Proceedings of the Conference on Major Trends in Superconductivity in the New Millennium (MTSC 2000), Klosters, Switzerland, 31 March 2000 – 6 April 2000, Journal of Superconductivity: Incorporating Novel Magnetism 13, 981 (2000).

High-Temperature Superconductivity is Charge-Reservoir Superconductivity, John D. Dow, Howard A. Blackstead and Dale R. Harshman, Invited Paper, in Proceedings of the Conference on Phase Transitions and Self-Organization in Electronic and Molecular Networks, Cambridge University, United Kingdom, 11-14 July 2000, to be published in Phase Transitions and Self-Organization in Electronic and Molecular Networks, edited by J. C. Phillips and M. F. Thorpe, (Kluwer-Plenum, 2001), pp 403-412.

The Case Against Cuprate-Plane Superconductivity, John D. Dow, Howard A. Blackstead and Dale R. Harshman, Invited Paper, in Proceedings of the 3rd International Conference on Stripes and High-T_CSuperconductivity (STRIPES 2000), Rome, Italy, 24-30 September 2000, Edited by Antonio Bianconi, International Journal of Modern Physics B 14, 3444 (2000).

Superconductivity and Magnetism in Sr₂YRu_1-uCu_uO₆ and Ba₂GdRu_1-uCu_uO₆, Dale R. Harshman, W. J. Kossler, A. J. Greer, C. E. Stronach, D. R. Noakes, E. Koster, M. K. Wu, F. Z. Chien, H. A. Blackstead, D. B. Pulling and J. D. Dow, Invited Paper, in Proceedings of the Third International Conference on New Theories, Discoveries, and Applications of Superconductors and Related Materials (New3SC-3), Honolulu, Hawaii, USA, 15-19 January 2001, Physica C 364-365, 392 (2001).

High-Temperature Superconductivity: the role of oxide layers, John D. Dow, Howard A. Blackstead and Dale R. Harshman, Invited Paper, in Proceedings of the Third International Conference on New Theories, Discoveries, and Applications of Superconductors and Related Materials (New3SC-3), Honolulu, Hawaii, USA, 15-19 January 2001, Physica C 364-365, 74 (2001).

Magnetic Resonance and Mossbauer Studies of GdSr₂Cu₂RuO₈, H. A. Blackstead, J. D. Dow, D. R. Harshman and D. B. Pulling, Invited Paper, in Proceedings of the Third International Conference on New Theories, Discoveries, and Applications of Superconductors and Related Materials (New3SC-3), Honolulu, Hawaii, USA, 15-19 January 2001, Physica C 364-365, 305 (2001).

New Picture of a High-Temperature Superconductivity, John D. Dow and Dale R. Harshman, in Proceedings of the 2001 SNS Meeting, Chicago, Illinois., USA, 13-17 May 2001, Physics and Chemistry of Solids, 63, 2309 (2002).

Origin of High-Temperature Superconductivity, in Proceedings of the Conference on Strongly Correlated Electron Systems (SCES 2001), Ann Arbor, Michigan, USA, 6-10 August 2001, John D. Dow and Dale R. Harshman, Physica B 312-313, 53 (2002).

Ruthenate and Cuprate High-T_C Superconductivity, John D. Dow and Dale R. Harshman, in Proceedings of the International Conference on Superconductivity, CRM and Related Materials: Novel Trends (SCRM 2002), Giens, France, 1-8 June 2002, Journal of Superconductivity 15, 455 (2002).

Proofs that High-Temperature Superconductivity is in BaO, SrO or Interstitial-Oxygen Layers, and is S-Wave Paired and P-Type, John D. Dow and Dale R. Harshman, in Proceedings of the 10th international Ceramics Congress and 3rd Forum on New Materials (CIMTEC 2002), Florence, Italy 14-18 July 2002, edited by P. Vincenzini (Techna Publishers, S.Rr.L., Faenza, Italy).

High-Temperature Superconductivity: The hole-pairing is s-wave and the holes are on the SrO, BaO or interstitial oxygen, John, D. Dow and Dale R. Harshman, in Proceedings of the 2002 International Conference on the Physics and Chemistry of Molecular and Oxide Superconductors (MOS 2002), Hsinchu, Taiwan, 13-18 August 2002, Journal of Low Temperature Physics 131, 483 (2003).

SrO and BaO High-Temperature Superconductivity, John D. Dow and Dale R. Harshman, in Proceedings of the 23rd International Conference on Low Temperature Physics (LT23), Hiroshima, Japan, 20-27 August 2002, Physica C 388-389, 447 (2003).

Locus of High-Temperature Superconductivity, John D. Dow and Dale R. Harshman, Invited Paper, in Proceedings of the Fourth International Conference on New Theories, Discoveries, and Applications of Superconductors and Related Materials (New3SC-4), San Diego, California, 16-21 January 2003, International Journal of Modern Physics B 17, 3310 (2003).

Verification of Nodeless Superconductivity Pairing in Single-Crystal YBa₂Cu₃O₇, Dale R. Harshman, W. J. Kossler, X. Wan, A. T. Fiory, A. J. Greer, D. R. Noakes, C. E. Stronach, E. Koster, A. Erb and John D. Dow, Invited Paper, in Proceedings of the Fourth International Conference on New Theories, Discoveries, and Applications of Superconductors and Related Materials (New3SC-4), San Diego, California, 16-21 January 2003, International Journal of Modern Physics B 17, 3582 (2003).

High-Temperature Superconductivity, John D. Dow and Dale R. Harshman, Invited Paper, in Proceedings of the International Workshop on Unconventional Superconductors (U-Super), Campinas, Brazil, 20-24 May 2003 Brazilian Journal of Physics 33, 681 (2003).

Non-Cuprate-Planar Superconductivity, John D. Dow and Dale R. Harshman, in Proceedings of the International Conference on Dynamic Inhomogeneities in Complex Oxides, Bled, Slovinia, 14-20 June 2003 Journal of Superconductivity 17, 179 (2004).

YBa₂Cu₃O₇ is an S-Wave Superconductor, Dale R. Harshman and John D. Dow, in Proceedings of the 7th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors (M2S-RIO), Rio de Janeiro, Brazil, 25-30 May 2003, Physica C 408-410, 361 (2004).

Nodeless Pairing State Symmetry in YBa₂Cu₃O₇, Dale R. Harshman, John D. Dow, W. J. Kossler, A. T. Fiory, A. J. Greer, D. R. Noakes, C. E. Stronach and E. Koster, Invited Paper, Symposium on Emerging Mechanisms for High Temperature Superconductivity (SEMHTS), Miami, Florida, 11-16 January 2004. New Challenges in Superconductivity: Experimental Advances and Emerging Theories, NATO Science Series II: Mathematics, Physics and Chemistry, Vol. 183, Edited by J. Ashkenazi, M. V. Erimin, J. L. Cohn, I. Eremin, D. Manske, D. Pavuna and F. Zuo, p. 129 (Springer, Berlin, New York, 2005).

High-Temperature Superconductivity of Oxides, John D. Dow and Dale R. Harshman, Invited Paper, Symposium on Emerging Mechanisms for High Temperature Superconductivity (SEMHTS), Miami, Florida, 11-16 January 2004. New Challenges in Superconductivity: Experimental Advances and Emerging Theories, NATO Science Series II: Mathematics, Physics and Chemistry, Vol. 183, Edited by J. Ashkenazi, M. V. Erimin, J. L. Cohn, I. Eremin, D. Manske, D. Pavuna and F. Zuo, p. 49 (Springer, Berlin, New York, 2005).

Fluxon Pinning in the Nodeless Pairing State of Superconducting YBa₂Cu₃O₇, A. T. Fiory, Dale R. Harshman, J. Jung, I.-Y. Isaac, W. J. Kossler, X. Wan, A. J. Greer, D. R. Noakes, C. E. Stronach, E. Koster and John D. Dow, Invited Paper, in Proceedings of the 133^rd Annual Meeting of the Minerals, Metals, Materials Society (TMS), Charlotte, North Carolina, 14-18 March 2004, Journal of Electronic Materials, Journal of Electronic Materials 34, 474 (2005).

The Discrepancy Between Muon Spectroscopy and Scanning Tunneling Microscopy and Photoemission: YBa₂Cu₃O₇ and Bi₂Sr₂CaCu₂O₈, John D. Dow and Dale R. Harshman, Invited Paper, in Proceedings of the Fifth International Conference on New Theories, Discoveries, and Applications of Superconductors and Related Materials (New3SC-5), Chongqing, China, 10-15 June 2004, International Journal of Modern Physics B 19, 37 (2005).

Thermal Conductivity of YBa₂Cu₃O₇: s-wave interpretation, Dale R. Harshman and John D. Dow, Invited Paper, in Proceedings of the Fifth International Conference on New Theories, Discoveries, and Applications of Superconductors and Related Materials (New3SC-5), Chongqing, China, 10-15 June 2004,International Journal of Modern Physics B 19, 147 (2005).

The True Nature of High Temperature Superconductivity, John D. Dow, Dale R. Harshman and Anthony T. Fiory, 24th International Conference on Low Temperature Physics, Orlando, Florida, 10 – 17 August 2005, AIP Conference Proceedings 850, 555 (2006).

Nature of High-Temperature Superconductivity, John D. Dow and Dale R. Harshman, Invited Paper, in Proceedings of the 33rd Conference on the Physics and Chemistry of Semiconducting Interfaces (PCSI-33), Cocoa Beach, Florida 15-19 January (2006), Journal of Vacuum Science and Technology B 24, 1977 (2006).

High-T_C Superconductivity in Cuprates and Ruthenates, John D. Dow, Dale R. Harshman and Anthony T. Fiory, Invited Paper, in Proceedings of Conference on Electron Correlation in New Materials and Nanosystems, NATO Advanced Research Workshop, Yalta, Crimea, Ukraine, 19-23 Sept. 2005, NATO Science Series II: Mathematics, Physics and Chemistry, Vol. 241: Electron Correlation in New Materials and Nanosystems, edited by .Kurt Scharnberg and Sergi Kruchinin (Springer, 2007).

Alkaline-Earth Layer High-Temperature Superconductivity, John D. Dow and Dale R. Harshman, in Proceedings of the 8th International Conference on Materials and Mechanisms of Superconductivity and High Temperature Superconductors (M2S-HTSC-VIII), Dresden, Germany 9-14 July 2006, Physica C 460-462, 499 (2007).

BaO Planes, Not CuO₂ Planes, Contain High-T_C Superconductivity, John D. Dow and Dale R. Harshman, Invited Paper, in Proceedings of the Sixth International Conference on New Theories, Discoveries, and Applications of Superconductors and Related Materials (New3SC-6), Sidney, Australia, 9-11 January 2007, International Journal of Modern Physics B 21, 3086 (2007).

Elements of Modern High-Temperature Superconductivity, John D. Dow and Dale R. Harshman, in Proceedings of NATO Advanced Research Workshop, Electron Transport in Nanosystems (ETN-2007 ), Yalta, Ukraine, 17-21 September 2007, NATO Science for Peace and Security Series B: Physics and Biophysics, Electron Transport in Nanosystems, edited by J. Bonca and S. K. Krunchinin (Springer, The Netherlands, 2008).

Symmetry of Superconductivity in YBa₂Cu₃O₇: s or d, John D. Dow, Dale R. Harshman and Anthony T. Fiory, Invited Paper, in Proceedings of Seventh International Conference on New Theories, Discoveries, and Applications of Superconductors and Related Materials (New3SC-7), Beijing, China, 13-16 May 2009, Journal of Superconductivity and Novel Magnetism 23, 641 (2010).

Effects of Vortex Pinning on the Temperature Dependence of the Magnetic Field Distributions in Superconductors, W. J. Kossler, A. J. Greer, D. R. Harshman, C. E. Stronach, A. C. Shockley and M. Shinn, in Proceedings of the 12th International Conference on Muon Spin Rotation and Resonance (μSR2011), Cancun, Mexico, 16-20 May 2011, Physics Procedia 30, 245 (2012).

Invited Talks more

Muonium on Silica Surfaces, D. R. Harshman, Invited Talk, µSR Journal Seminar, Department of Physics, University of California at Berkeley, Berkeley, California, USA, 16 February 1983.

Behavior of Muonium on SiO₂ Surfaces, D. R. Harshman, Invited Talk, Solid State Seminar Series, Department of Physics, The University of British Columbia, Vancouver, B.C., Canada, 28 February 1985.

Muonium on Silica Surfaces, D. R. Harshman, Invited Talk, AT&T Bell Laboratories, Murray Hill, New Jersey, USA, 4 April 1985.

The Interaction of Muonium with Silica Surfaces, D. R. Harshman, Invited Talk, Physics and Astronomy Seminar Series, Department of Physics, Western Washington University, Bellingham, Washington, USA, 15 May 1985.

Muonium on Surfaces, D. R. Harshman, Invited Talk, European Workshop on the Spectroscopy of Sub-Atomic Species in Non-Metallic Solids, Vitry-sur-Seine, France, 3 – 7 September 1985.

The Interactions of Muonium with Surfaces, D. R. Harshman, Invited Talk, Lawrence Livermore National Laboratory, Livermore, California, USA, 21 October 1985.

Ultra-Slow Muon Production, D. R. Harshman, Invited Talk, Workshop on New Methods and Applications of µSR, The University of British Columbia, Vancouver, B.C., Canada, 21-23 August 1985.

Muon/Muonium Surface Interactions, D. R. Harshman, Invited Talk, µSR-86 Conference, Uppsala, Sweden, 23-27 June 1986 [Cross Ref: Paper].

Slow Muon Physics, D. R. Harshman, Invited Talk, NATO Advanced Research Workshop on Atomic Physics with Positrons, London, England 15 – 18 July 1987 [Cross Ref: Paper].

µ⁺SR and Positron Annihilation Spectroscopy in YBa₂Cu₃O_7-d and La_2-xSr_xCuO₄, D. R. Harshman, Invited Talk, Department of Physics, University of Maryland, College Park, Maryland, USA, 7 March 1988.

µ⁺SR and Positron Annihilation Spectroscopy in YBa₂Cu₃O_7-d and La_2-xSr_xCuO₄, D. R. Harshman, Invited Talk, AT&T Bell Laboratories, Murray Hill, New Jersey, USA, 11 March 1988.

Spin Dynamics and Superconductivity in Cu-Oxides, D. R. Harshman, Invited Talk, APS Meeting, St. Louis, Missouri, USA, 20 – 24 March 1989.

Polarization and Resonance in Magnetic X-Ray Scattering, E. D. Isaacs, D. R. Harshman, D. B. McWhan, L. D. Gibbs, D. Mills and C. Vettier, Invited Talk, Department of Physics, Cornell University, Ithaca, New York, USA, 14 June 1988.

Polarization Analysis of X-Ray Magnetic Scattering, Doon Gibbs, M. Blume, D. R. Harshman and D. B. McWhan, Invited Talk, Third International Conference on Synchrotron Radiation Instrumentation, Tsukuba, Japan, 4 September 1988 [Cross Ref: Paper].

Magnetic Penetration Depth, Flux Motion, and Disorder in the High-T_CCuprates, D. R. Harshman, Invited Talk, Department of Applied Physics, Stanford University, Stanford, California, USA, 7 December 1989.

Evidence for a Fermi Surface in Bi₂Sr₂CaCu₂O_8+δ Measured by 2D-ACAR, L. P. Chan, D. R. Harshman, K. G. Lynn, S. Massidda and D. B. Mitzi, Invited Talk, Conference on the Fermiology of High-T_CSuperconductors, Argonne National Laboratory, Argonne, Illinois, USA, 25 – 27 March 1991 [Cross Ref: Paper].

New Physics with the Muon and Positron Facilities Proposed at CEBAF, D. R. Harshman and A. P. Mills, Jr., Invited Talk, CEBAF, Newport-News, Virginia, USA, 2 July 1991.

The Penetration Depth and Pairing State in Selected Organic Superconductors, D. R. Harshman, Invited Talk, Gordon Research Conference on Organic Superconductors, Irsee, Germany, 22 – 27 September 1991.

On the Nature of High-T_C Superconductivity, D. R. Harshman, Invited Talk, AT&T Bell Laboratories, Murray Hill, New Jersey, USA, 9 October 1991.

Search for an “Ideal” High-T_C Superconductor, D. R. Harshman and A. P. Mills, Jr., Invited Talk, Department of Physics, Brandeis University, Waltham Massachusetts, USA, 29 October 1991.

Optimization and Disorder in High-T_C Superconductors, D. R. Harshman, Invited Talk, Brookhaven National Laboratories, Upton, New York, USA, 30 January 1992.

Existence and Nature of the Fermi Surface in Bi₂Sr₂CaCu₂O_8+δ and Related Materials, D. R. Harshman, Invited Talk, APS Meeting, Indianapolis, Indiana, USA, 15 – 20 March 1992.

Slow Muon Physics: Applications to Problems in Superconductivity, D. R. Harshman, Invited Talk, International Workshop on Low Energy Muon Science (LEMS ’93), Sante Fe, New Mexico, USA, 4 – 8 April 1993, M. Leon, Editor [Cross Ref: Paper].

High-T_C Superconductivity: Applications of µ⁺SR and Slow µ⁺ Beams, D. R. Harshman, Invited Talk, International School of Physics, Enrico Fermi Course on Positron Spectroscopy of Solids, Varenna, Italy, 6 – 16 July 1993 [Cross Ref: Paper].

The Nature of High-T_C Superconductivity: Fact and Fantasy, D. R. Harshman, Invited Talk, Department of Physics, Virginia Commonwealth University, Richmond, Virginia, USA, 22 October 1993.

Muon Spin Rotation (µ⁺SR) and the Nature of High-T_C Superconductivity, D. R. Harshman, Invited Talk, Department of Physics, The University of Utah, Salt Lake City, Utah, USA, 16 August 1996.

Muon Spin Rotation in Sr₂YRu_1-uCu_uO₆, D. R. Harshman, Invited Talk, 2^nd Annual Conference on New Theories, Discoveries and Applications of Superconductors and Related Materials, Las Vegas, Nevada, USA, 31 May – 3 June 1999 [CrossRef: Paper].

High-Temperature Superconductivity is Charge-Reservoir Superconductivity, John D. Dow, Howard A. Blackstead and Dale R. Harshman, Invited Talk, Conference on Phase Transitions and Self-Organization in Electronic and Molecular Networks, Cambridge University, UK, 11 – 14 July 2000 [Cross-Ref: Paper].

The Case Against Cuprate-Plane Superconductivity, John D. Dow, Howard A. Blackstead and Dale R. Harshman, Invited Talk, 3rd International Conference on Stripes and High-T_C Superconductivity (STRIPES 2000), Rome, Italy, 24-30 September 2000 [Cross-Ref: Paper].

Feasibility of ¹²⁵Xe Implantation at TRIUMF for Preparation of ¹²⁵I Brachytherapy, J. Vincent, T. Ruth, A. Zyuzin, J. D’Auria, D. Ottewell and D. R. Harshman, Invited Talk, Pacifichem 2000 Meeting, Honolulu, Hawaii, 14-19 December 2000 [Cross-Ref. Patent].

Magnetic Resonance and Mossbauer Studies of GdSr₂Cu₂RuO₈, H. A. Blackstead, J. D. Dow, D. R. Harshman and D. B. Pulling, Third International Conference on New Theories, Discoveries, and Applications of Superconductors and Related Materials (New3SC-3), Honolulu, Hawaii, USA, 15-19 January 2001 [Cross-Ref: Paper].

Superconductivity and Magnetism in Sr₂YRu_1-uCu_uO₆ and Ba₂GdRu_1-uCu_uO₆, Dale R. Harshman, W. J. Kossler, A. J. Greer, C. E. Stronach, D. R. Noakes, E. Koster, M. K. Wu, F. Z. Chien, H. A. Blackstead, D. B. Pulling and John D. Dow, Invited Talk, Third International Conference on New Theories, Discoveries, and Applications of Superconductors and Related Materials (New3SC-3), Honolulu, Hawaii, USA, 15-19 January 2001 [Cross-Ref: Paper].

High-TemperatureSuperconductivity: The Role of BaO, SrO and Interstitial-Oxygen, John D. Dow, Howard A. Blackstead and Dale R. Harshman, Third International Conference on New Theories, Discoveries, and Applications of Superconductors and Related Materials (New3SC-3), Honolulu, Hawaii, USA, 15-19 January 2001 [Cross-Ref: Paper].

Recent Progress in the Study of Ruthenate High Temperature Superconductivity, H. A. Blackstead, J. D. Dow, D. R. Harshman, P. J. McGinn, N. A. Licata, W. B. Yelon, I. Felner, D. Wang and Z. Ren, Invited Talk, International Conference on Modern Problems of Superconductivity, Yalta, Crimea, Ukraine, 9-14 September 2002.

Locus of High-Temperature Superconductivity, John D. Dow and Dale R. Harshman, Invited Talk, Fourth International Conference on New Theories, Discoveries, and Applications of Superconductors and Related Materials (New4SC-3), San Diego, California, 16-21 January 2003 [Cross-Ref. Paper].

Verification of Nodeless Superconductivity Pairing in Single-Crystal YBa₂Cu₃O₇,Dale R. Harshman, W. J. Kossler, X. Wan, A. T. Fiory, A. J. Greer, D. R. Noakes, C. E. Stronach, E. Koster, A. Erb and John D. Dow, Invited Talk, Fourth International Conference on New Theories, Discoveries, and Applications of Superconductors and Related Materials (New4SC-3), San Diego, California, 16-21 January 2003 [Cross-Ref. Paper].

High-Temperature Superconductivity, John D. Dow and Dale R. Harshman, Invited Talk,International Workshop on Unconventional Superconductors (U-Super), Campinas, Brazil, 20-24 May 2003 [Cross-Ref. Paper].

Nodeless Pairing State Symmetry in YBa₂Cu₃O₇, Dale R. Harshman, John D. Dow, W. J. Kossler, A. T. Foiry, A. J. Greer, D. R. Noakes, C. E. Stronach and E. Koster, Symposium on Emerging Mechanisms for High Temperature Superconductivity (SEMHTS), Miami, Florida, 11-16 January 2004 [Cross-Ref. Paper].

High-Temperature Superconductivity of Oxides, John D. Dow and Dale R. Harshman, Symposium on Emerging Mechanisms for High Temperature Superconductivity (SEMHTS), Miami, Florida, 11-16 January 2004 [Cross Ref. Paper].

Fluxon Pinning in the Nodeless Pairing State of Superconducting YBa₂Cu₃O₇, A. T. Fiory, Dale R. Harshman, J. Jung, I.-Y. Isaac, W. J. Kossler, X. Wan, A. J. Greer, D. R. Noakes, C. E. Stronach, E. Koster and John D. Dow, Invited Talk, The 133^rd Annual Meeting of the Minerals, Metals, Materials Society (TMS), Charlotte, North Carolina, 14-18 March 2004 [Cross-Ref. Paper] (slides).

The Locus of Superconductivity in the Cuprates and the Ruthenates, John D. Dow and Dale R. Harshman, Invited Talk, Conference on Dynamical Energy Landscapes and Functional Systems, Sante Fe, New Mexico, USA, 28 March – 3 April 2004.

The Discrepancy Between Muon Spectroscopy and Scanning Tunneling Microscopy and Photoemission: YBa₂Cu₃O₇ and Bi₂Sr₂CaCu₂O₈, John D. Dow and Dale R. Harshman, Invited Talk, Fifth International Conference on New Theories, Discoveries, and Applications of Superconductors and Related Materials (New3SC-5), Chongqing, China, 10-15 June 2004.

Thermal Conductivity of YBa₂Cu₃O₇: s-wave interpretation, Dale R. Harshman and John D. Dow, Invited Talk, Fifth International Conference on New Theories, Discoveries, and Applications of Superconductors and Related Materials (New3SC-5), Chongqing, China, 10-15 June 2004 [Cross Ref. Paper].

High-T_C Superconductivity in Cuprates and Ruthenates, John D. Dow, Dale R. Harshman and Anthony T. Fiory, Invited Talk, Conference on Electron Correlation in New Materials and Nanosystems, NATO Advanced Research Workshop, Yalta, Crimea, Ukraine, 19-23 Sept. 2005.

Nature of High-Temperature Supercondeuctivity, John D. Dow and Dale R. Harshman, Invited Talk,33rd Conference on the Physics and Chemistry of Semiconducting Interfaces (PCSI-33), Cocoa Beach, Florida 15-19 January (2006).

BaO Planes, Not CuO₂ Planes, Contain High-T_C Superconductivity, John D. Dow and Dale R. Harshman, Invited Talk, Sixth International Conference on New Theories, Discoveries, and Applications of Superconductors and Related Materials (New3SC-6), Sidney, Australia, 9-11 January 2007 [Cross Ref. Paper].

Elements of Modern High-Temperature Superconductivity, John D. Dow and Dale R. Harshman, Invited Talk, NATO Advanced Research Workshop, Electron Transport in Nanosystems (ETN-2007 ), Yalta, Ukraine, 17-21 September 2007, NATO Science Series: Electron Transport in Nanosystems to be published [Cross Ref. Paper].

Symmetry of Superconductivity in YBa₂Cu₃O₇: s or d, John D. Dow, Dale R. Harshman and Anthony T. Fiory, Invited Talk, Seventh International Conference on New Theories, Discoveries, and Applications of Superconductors and Related Materials (New3SC-7), Beijing, China, 13-16 May 2009 [Cross Ref. Paper].

Abstracts more

Positive Muon Spin Rotation in Magnetic-Superconducting SmRh₄B₄, C. Y. Huang, Z. Fisk, C. W. Clawson, K. M. Crowe, S. S. Rosenblum, J. H. Brewer, D. R. Harshman, S. E. Lambert, M. S. Torikachvili and M. B. Maple, APS Meeting, Dallas, Texas, USA, March 1982.

Magnetic Susceptibility, Proton NMR and Muon Spin Rotation (µSR) Studies of Unsupported Platinum Catalysts with Adsorbed H and O, R. F. Marzke, W. S. Glaunsinger, K. B. Rawlings, P. Van Rheenen, M. McKelvy, J. H. Brewer, D. R. Harshman and R. F. Kiefl, APS Meeting, Dallas, Texas, USA, March 1982.

Muonium on Bare Silica Surfaces, D. R. Harshman, R. F. Kiefl and J. H. Brewer,Western Regional Nuclear Physics Conference, Banff, Alberta, Canada, February 1982.

Muonium on Bare Silica Surfaces, D. R. Harshman, R. Keitel, R. F. Kiefl, M. Senba and J. H. Brewer, 2^ndTrieste International Symposium on Statistical Mechanics of Adsorption, Trieste, Italy, July 1982.

Observation of H NMR and of Muon Spin Rotation in Unsupported Platinum, R. F. Marzke, W. S. Glaunsinger, K. B. Rawlings, P. Van Reenen, M. McKelvy, J. H. Brewer, D. R. Harshman and R. F. Kiefl, California Catalysis Society – Annual Fall Meeting, Irvine, California, USA, October 1982.

Behavior of Muonium on Silica Surfaces, D. R. Harshman, J. H. Brewer, M. Senba, R. Keitel and E. J. Ansaldo, CAP Meeting, University of Victoria, Victoria, B.C., Canada, June 1983.

Spin Relaxation in YRh₄B₄ and SmRh₄B₄, E. J. Ansaldo, D. R. Harshman, J. H. Brewer, C. Y. Huang, K. M. Crowe and S. S. Rosenblum, CAP Meeting, University of Victoria, B.C., Canada, June 1983.

Diffusion and Trapping of Muonium on Silica Surfaces, D. R. Harshman, J. H. Brewer, M. Senba, R. Keitel and E. J. Ansaldo, California Catalysis Society – Annual Fall Meeting, Brea, California, USA, October 1983.

Muonium on Amorphous SiO₂ Surfaces, D. R. Harshman, J. H. Brewer, R. Keitel, M. Senba, J. M. Bailey and E. J. Ansaldo, CAP Meeting, Universite de Sherbrooke, Sherbrooke, Quebec, Canada, June 1984.

Giant Muon Knight Shifts in Antimony Alloys, J. H. Brewer, D. R. Harshman, E. Koster, S. R. Kreitzman and D. Ll. Williams, CAP Meeting, Universite de Sherbrooke, Sherbrooke, Quebec, Canada, June 1984.

Muon Spin Relaxation and Crystalline Electric Field Effects in RERh₄B₄, D. R. Noakes, E. J. Ansaldo, J. H. Brewer, C. Y. Huang and D. R. Harshman, CAP Meeting, Universite de Sherbrooke, Sherbrooke, Quebec, Canada, June 1984.

Muonium Diffusion on Amorphous SiO₂ Surfaces, D. R. Harshman, J. H. Brewer, R. Keitel, M. Senba, J. M. Bailey and E. J. Ansaldo, International Chemical Congress of Pacific Basin Societies, Honolulu, Hawaii, USA, 16 – 21 December 1984.

Measurement of the Reaction Rate of Muonium with the Surface of a Supported Platinum Catalyst by Muonium Spin Rotation (MSR), R. F. Marzke, W. S. Glaunsinger, D. R. Harshman, E. J. Ansaldo, R. Keitel, D. R. Noakes, M. Senba and J. H. Brewer, APS Meeting, Baltimore, Maryland, USA, March 1985.

Measurement of the Reaction Rate of Muonium with the Surface of a Supported Platinum Catalyst by Muonium Spin Rotation (MSR), R. F. Marzke, W. S. Glaunsinger, D. R. Harshman, E. J. Ansaldo, R. Keitel, D. R. Noakes, M. Senba and J. H. Brewer, California Catalysis Society – Annual Spring Meeting, Menlo Park, California, USA, April 1985.

Production of Muonium in Vacuum from Silica Powders, G. M. Marshall, G. A. Beer, T. Bowen, Z. Gelbart, P. Halverson, D. R. Harshman, K. R. Kendall, A. R. Kunselman, G. R. Mason, A. Olive and J. B. Warren, in Proceedings of the µSR-86 Conference, Uppsala, Sweden, 23 -27 June 1986.

Temperature and Loading Dependence of Muonium Relaxation Rates in Silica-Supported Pt Catalysts, R. J. Marzke, D. R. Harshman, E. J. Ansaldo, R. Keitel, M. Senba, D. R. Noakes and J. H. Brewer, APS Meeting, New York, New York, USA, March 1987.

Generation of Slow Positive Muons from Solid Rare-Gas Moderators, D. R. Harshman, A. P. Mills, Jr., J. L. Beveridge, K. R. Kendall, G. D. Morris, M. Senba, J. B. Warren, A. S. Rupaal and J. H. Turner, XI International Conference on Particles and Nuclei, Kyoto, Japan, April 1987.

µ⁺SR in La_2-xSr_xCuO₄ and YBa₂Cu₃O₇, D. R. Harshman, G. Aeppli, G. P. Espinosa, A. S. Cooper, J. P. Remeika, L. F. Schneemeyer, J. V. Waszczak, B. Batlogg, E. J. Ansaldo, J. H. Brewer, R. F. Kiefl, G. Luke, T. Riseman and D. R. Noakes, APS Meeting, New Orleans, Louisianna, USA, 21 – 25 March 1988.

Positron Studies in Single-Crystal YBa₂Cu₃O₇, Y. C. Jean, D. R. Harshman, M. J. Fluss, L. F. Schneemeyer, A. L. Wachs, J. V. Waszczak, R. L. Howell, APS Meeting, New Orleans, Louisiana, USA, 21 – 25 March 1988.

Electron Momentum Density Measurements of Single-Crystal La₂CuO₄, A. L. Wachs, P. Turchi, D. R. Harshman, Y. C. Jean, R. H. Howell, M. J. Fluss, J. Remeika, A. Cooper, and R. M. Fleming, APS Meeting, New Orleans, Louisiana, USA, 21 – 25 March 1988.

Polarization and Resonance Properties of Magnetic X-Ray Scattering in Holmium, Doon Gibbs, D. R. Harshman, D. B. McWhan, D. Mills, and C. Vettier, APS Meeting, New Orleans, Louisiana, USA, 21 – 25 March 1988.

Electronic Structure Investigations of High-T_C Materials by Positron Annihilation Spectroscopy, A. L. Wachs, P. E. A. Turchi, R. Howell, M. J. Fluss, Y. C. Jean and D. R. Harshman, MRS Meeting, Reno, Nevada, USA, 5 – 8 April 1988.

Magnetic Penetration Depth in the Organic Superconductor κ-[BEDT-TTF]₂Cu[NCS]₂, D. R. Harshman, R. N. Kleiman, R. C. Haddon, S. V. Chichester-Hicks, M. L. Kaplan, L. W. Rupp, Jr, T. Pfiz, D. Ll. Williams and D. B. Mitzi, APS Meeting, Anaheim, California, USA, 12 – 16 March 1990.

Muon Spin Rotation Studies of Reactions of Muonium Adsorbates with Platinum Metal Aggregates on Pure Silica Powder Supports, R.F. Marzke, P.W. Percival, J.H. Brewer, R. Keitel, D.G. Fleming, E. J. Ansaldo, M. Senba, D.R. Noakes and D.R. Harshman, Third North American Chemical Congress, Toronto, Canada, 5 – 10 June 1988.

Flux-Lattice Dynamics in Bi₂Sr₂CaCu₂O_8+δ, D. R. Harshman, R. N. Kleiman, G. Aeppli, G. P. Espinosa, D. B. Mitzi, T. Pfiz and D. Ll. Williams, APS Meeting, Anaheim, California, USA, 12 – 16 March 1990.

Positron 2D-ACAR Measurements of Bi₂Sr₂CaCu₂O_8+δ, L. P. Chan, D. R. Harshman, K. G. Lynn and D. B. Mitzi, APS Meeting, Anaheim, California, USA, 12 – 16 March 1990.

Magnetic Penetration Depth and Pairing State of UPt₃, C. Broholm, R. N. Kleiman, G. Aeppli, D. R. Harshman, D. J. Bishop, E. Bucher, D. Ll. Williams, R. H. Heffner, and E. J. Ansaldo, APS Meeting, Anaheim, California, USA, 12 – 16 March 1990.

Magnetic Penetration Depth and Flux-Dynamics in Single-Crystal Bi₂Sr₂CaCu₂O_8+δ, D. R. Harshman, R. N. Kleiman, M. Inui, G. P. Espinosa, D. B. Mitzi, A. Kapitulnik, T. Pfiz and D. Ll. Williams, APS Meeting, Cincinnati, Ohio, USA, 17 – 21 March 1991.

Flux Lattice Disorder in High-T_C Superconductors Observed by Muon-Spin Rotation, A. T. Fiory and D. R. Harshman, APS Meeting, Cincinnati, Ohio, USA, 17 – 21 March 1991.

Application of Muons Spin Relaxation to Observe Vortex Dynamics in Superconductors, M. Inui and D. R. Harshman, APS Meeting, Cincinnati, Ohio, USA, 17 – 21 March 1991.

Positron Annihilation Study of Selected Tl-Based Superconducting Systems, L. P. Chan, K. G. Lynn,D. R. Harshman, L. R. Monar, S. Massidda, Jaejun Yu, A. J. Freeman, C. P. Tigges, B. Morosin, D. S. Ginley and E. L. Venturini, APS Meeting, Indianapolis, Indiana, 16-20 March 1992.

Correlations Among the 2D Electronic Parameters of Optimized High-T_CSuperconductors, D. R. Harshman and A. P. Mills, Jr., APS Meeting, Indianapolis, Indiana, USA, 16 – 20 March 1992.

Electronic Structure Measurements of the Organic Superconductor κ-[BEDT-TTF]₂Cu[NCS]₂ via Positron Annihilation, L. P. Chan, K. G. Lynn, D. R. Harshman, R. C. Haddon and M. L. Kaplan, APS Meeting, Seattle, Washington, USA, , 22 – 26 March 1993.

Flux-Lattice Motion and Longitudinal Disordering in Anisotropic Superconductors, D. R. Harshman and A. T. Fiory, APS Meeting, Seattle, Washington, USA, 22 – 26 March 1993.

Pair Momentum Distribution of Native Defects in SI GaAs Under Photoexcitation, J. P. Peng, M. T. Umlor, K. G. Lynn, D. J. Keeble and D. R. Harshman, APS Meeting, Pittsburg, Pennsylvania, USA, 21 – 25 March 1994.

Study of the Electronic Structure of the SiO₂/Si Buried Interface Using Positron Annihilation (2D-ACAR), J. P. Peng, K. G. Lynn, P. Asoka-Kumar, D. P. Becker and D. R. Harshman, APS Meeting, San Jose, California, USA, 21 – 25 March 1995.

Study of the Electronic Structure of the SiO₂/Si Buried Interface Using Positron Annihilation (2D-ACAR), J. P. Peng, K. G. Lynn, P. Asoka-Kumar, D. P. Becker and D. R. Harshman, The Fifth International Conference on the Formation of Semiconductor Interfaces, Princeton University, Princeton, New Jersey, USA, 26 – 30 June 1995.

Study of the Defect Structure of the SiO₂/Si Interface Using Positron Annihilation, J. P. Peng, K. G. Lynn, P. Asoka-Kumar, D. P. Becker, D. R. Harshman and A. T. Fiory, Conference on Physics and Chemistry of Semiconductor Interfaces, La Jolla, California, USA, 21 – 23 January 1996.

Magnetic Transparency of the ab Planes of BSCCO and the Disorder and Dynamics of the Pancake Vortices, W. J. Kossler, K. G. Petzinger, X. Wan, Y. Dai, A. J. Greer, D. Ll. Williams, E. Koster, D. R. Harshman and D. B. Mitzi, APS Meeting, Los Angeles, California, USA, 16-20 March 1998 (abstract).

Magnetism and Superconductivity of Rutheno-Cuprates, John D. Dow, Howard A. Blackstead andDale R. Harshman, Symposium on Itinerant and Localized States in HTSC (SILS), Klosters, Switzerland, 6 April 2000 – 10 April 2000.

Magnetic Resonance, Muon Spin Rotation and Magnetization Measurements of GdSr_2Cu_2RuO_8, H. A. Blackstead, John D. Dow, D. R. Harshman, D. B. Pulling, Z. F. Ren, D. Z. Wang, APS Meeting, Seattle, Washington, 12-16 March 2001 (abstract).

Properties of the Superconducting Hole Condensate in Sr(2)YRu(1-u)Cu(u)O(6), Dale R. Harshman, W. J. Kossler, A. J. Greer, C. E. Stronach, E. Koster, Howard A. Blackstead, John D. Dow, M. K. Wu and F. Z. Chien, APS Meeting, Seattle, Washington, 12-16 March 2001 (abstract).

The Nature of High-Temperature Superconductivity, John D. Dow, Howard A. Blackstead and Dale R. Harshman, APS Meeting, Seattle, Washington, 12-16 March 2001 (abstract).

High-Temperature Superconductivity, John D. Dow and Dale R. Harshman, Gordon Conference on Superconductivity, Queen’s College, Oxford, UK, 9 – 14 September 2001.

The Case Against High-Temperature Superconductivity Originating in the Cuprate Planes, John D. Dow and Dale R. Harshman, APS Meeting, Indianapolis, Indiana, 18 – 22 March 2002 (abstract).

The Superconductivity of YBa₂Cu₃O₇ is in the BaO-Layers, Dale R. Harshman and John D. Dow, APS Meeting, Montreal, Quebec, Canada, 22-26 March 2004 (abstract).

Superconductivity is not in the Cuprate Planes, John D. Dow, Dale R. Harshman and Howard A. Blackstead, APS Meeting, Montreal, Quebec, Canada, 22-26 March 2004 (abstract).

Thermal Conductivity of YBa₂Cu₃O₇, Dale R. Harshman and John D. Dow, APS Meeting, Los Angeles, California, 21-25 March 2005 (abstract).

Feasibility of Superconductivity in Semiconductor Superlattices, Kenneth P. Walsh, Anthony T. Fiory, N. M. Ravindra, Dale R. Harshman and John D. Dow, APS Meeting, Baltimore, Maryland 13-17 March 2006 (abstract).

Nodeless Ground State Symmetry of YBa₂Cu₃O_7-δ, Dale R. Harshman, John D. Dow and Anthony T. Fiory, APS Meeting, Denver, Colorado 5-9 March 2007 (abstract).

Isotope Effect in High-T_C Superconductors, Dale R. Harshman, John D. Dow and Anthony T. Fiory, APS Meeting, New Orleans, Louisiana, 10-14 March 2008 (abstract) (slides).

High-Temperature Superconductivity: Status, John D. Dow, Dale R. Harshman and Anthony T. Fiory,APS Meeting, Pittsburgh, Pennsylvania, 16-20 March 2009 (abstract).

Theory of High-T_C Superconductivity: Accurate Predictions of T_C, Dale R. Harshman and Anthony T. Fiory, APS Meeting, Boston, Massachusetts, 27 February – 2 March, 2012 (abstract) [arXiv] [extended abstract].

Optimal High-T_C Superconductivity in Cs₃C₆₀, Dale R. Harshman and Anthony T. Fiory, APS Meeting, Baltimore, Maryland, 14-18 March, 2016 (abstract) [extended abstract] (slides).

Work included in Magazine Articles, Journal Highlights and Editorials

Discover Magazine: The Cinderella Particle, by Christian von Baeyer (1 Dec. 1993).

IOPscience LabTalk (no longer available online): High-temperature superconductivity theory accurately predicts transition temperatures (27 July 2011).

Journal of Physics: Condensed Matter | Highlights of 2011: Seminal paper included – Theory of High-T_C Superconductivity: Transition Temperature, Journal of Physics: Condensed Matter 23, 295701 (2011).

W&M | ScholarWorks: Compressed H₃S: Inter-sublattice Coulomb Coupling in a High-T_C Superconductor (2017); reprinted from Journal of Physics: Condensed Matter 29, 445702 (2017).

Wikipedia: Muon Spin Spectroscopy; low-energy muon beam.

Other Activities

Government Review Panels

Served on Department of Energy Peer Review Panel, Arlington, VA, 28-30 July 1992.
Served on Department of Energy Peer Review Panel, Arlington, VA, 1-3 September 1992.

Patents & Copyrights

Radioactive Ion (Implantation), J. Vincent, T. Ruth, A. Zyuzin, J. D’Auria, D. Ottewell and D. R. Harshman (TRIUMF Patent – application for arterial stents). Priority date for all applications: 12 Dec. 2001.

Country/Entity

World / WIPO
European Union
European Union
European Union
Canada
Mexico
France
Germany
United Kingdom
Japan
Korea
United States

Publ. No.

WO 03/053509
EP 1 946 796 A2
EP 1 946 797 A2
1463533
N/A
WO 03/053509
N/A
N/A
N/A
2005-513451
N/A
US 2005/0118098 A1

Application No.

PCT/US02/39557
07150325.4
07150329.6
02787004.7
CA 2,470,006
PA/a/2004/005655
02787004.7
02787004.7
02787004.7
2003-554265
10-2004-7008719
10/498,368

Filing Date

12 Dec 2002
21 Dec 2007
21 Dec 2007
9 Jul 2004
10 Jun 2004
11 Jun 2004
12 Dec 2002
12 Dec 2002
12 Dec 2002
11 May 2004
5 Jun 2004
14 Jan 2005

These patents were allowed to lapse in 2010.

Layered Ionic Superconductor, D. R. Harshman and A. T. Fiory

Country/Entity

United States

Patent ID

US 8,703,651 B2

Application No.

13/543,655

Filing Date

6 Jul 2012

Copyrighted Verse

Voices (Registration No. PAu 2-167-731, 24 February 1997)
False Winds of Hope (Registration No. PAu 2-095-422, 14 June 1996)
Faraday Hollander (Registration No. Registration No. TXu 232 915, 20 March 1986)

Professional memberships

American Physical Society

References

Dr. Anthony T. Fiory, Research Scientist in Physics
New Jersey Institute of Technology, Newark, New Jersey 07102
fiory@alum.mit.edu

Dr. William J. Kossler, Professor (Emeritus) of Physics
The College of William and Mary, Williamsburg, Virginia 23185
w jkoss@wm.edu

Dr. Peter B. Littlewood, Director
Argonne National Laboratory, Argonne, IL 60439
Professor of Physics, James Franck Institute
University of Chicago, Chicago, Illinois 76063
pblittlewood@anl.gov

Dr. James L. Smith, Chief Scientist & Fellow (Emeritus)
Los Alamos National Laboratory
Materials Technology: Metallurgy – MST-6
Los Alamos, New Mexico 87545
jlsmith@lanl.gov

Personal

Birth Date: 13 August 1956 | Honolulu, Hawaii

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