527 citations · 2.4k across the 24 of their papers we have counts for
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Negative thermal expansion of MgB in the superconducting state and anomalous behavior of the bulk Grüneisen function
J. J. Neumeier, T. Tomita, M. Debessai +4
The thermal expansion coefficient of MgB is revealed to change from positive to negative on cooling through the superconducting transition temperature . The Grüneisen…
Thermal Expansion and Compressibility in Superconducting NaxCoO2o4xD2O (x?1/3): Evidence for Pressure-Induced Charge Redistribution
J. D. Jorgensen, M. Avdeev, D. G. Hinks +2
We have performed thermal expansion and compressibility measurements on the recently discovered superconducting material NaxCoO2*4xD2O (x=1/3) using neutron powder diffraction over…
The effect of {11}^B substitution on the superconductivity in MgCNi3
T. Klimczuk, M. Avdeev, J. D. Jorgensen +1
The crystal structure of boron doped superconducting MgC_{1-x}{11}^B_{x}Ni_{3}, studied by powder neutron diffraction, is reported. The solubility limit of boron is determined to b…
Crystal Structure of the Sodium Cobaltate Deuterate Superconductor NaxCoO2o4xD2O (x=1/3)
J. D. Jorgensen, M. Avdeev, D. G. Hinks +2
Neutron and x-ray powder diffraction have been used to investigate the crystal structures of a sample of the newly-discovered superconducting sodium cobaltate deuterate compound wi…
Retention of Two-Band Superconductivity in Highly Carbon-Doped MgB2
H. Schmidt, K. E. Gray, D. G. Hinks +4
Tunneling data on MgB_{1.8}C_{0.2} show a reduction in the energy gap of the pi-bands by a factor of two from undoped MgB2 that is consistent with the Tc reduction, but inconsisten…
Crystal Chemistry of Carbon-Substituted MgB2
M. Avdeev, J. D. Jorgensen, R. A. Ribeiro +2
Neutron powder diffraction has been used to characterize a sample of C-substituted MgB2 synthesized from Mg and B4C (with isotopically enriched 11B). The sample is multiphase, with…
Dependence of the superconducting transition temperature of single- and polycrystalline MgB2 on hydrostatic pressure
S. Deemyad, T. Tomita, J. J. Hamlin +6
The dependence of Tc for MgB2 on purely hydrostatic or nearly hydrostatic pressure has been determined to 23 GPa for single-crystalline and to 32 GPa for polycrystalline samples, a…
Synthesis and Stoichiometry of MgB2
D. G. Hinks, J. D. Jorgensen, Hong Zheng +1
The system MgxB2 has been investigated to investigate possible nonstoichiometry in MgB2. When synthesized at 850oC, MgB2 is a line compound with a possible Mg vacancy content of ab…
Structure and Superconductivity in Zr-Stabilized, Nonstoichiometric Molybdenum Diboride
L. E. Muzzy, M. Avdeev, G. Lawes +5
The structure and physical properties of the Zr-stabilized, nonstoichiometric molybdenum diboride superconductor are reported. Good quality material of the diboride structure type…
Robust paramagnetism in Bi2-xMxRu2O7 (M=Mn,Fe,Co,Ni,Cu) pyrochlore
M. K. Haas, R. J. Cava, M. Avdeev +1
We report physical property characterization of Bi2-xMxRu2O7 pyrochlores, including magnetic suseptibility, resistivity, and Seebeck coefficients. The solid solution exists up to x…
Large Anisotropic Thermal Expansion Anomaly near the Superconducting Transition Temperature in MgB2
J. D. Jorgensen, D. G. Hinks, P. G. Radaelli +2
An anisotropic lattice anomaly near the superconducting transition temperature, Tc, was observed in MgB2 by high-resolution neutron powder diffraction. The a-axis thermal expansion…
Hydrostatic Pressure Dependence of the Superconducting and Structural Properties of MgB2
J. S. Schilling, J. D. Jorgensen, D. G. Hinks +4
In this paper we report parallel in situ neutron powder diffraction and Tc(P) measurements versus pressure on the same MgB2 sample in a He-gas apparatus to 0.6 GPa; in addition, we…
Identification and Characterization of Two Energy Gaps in Superconducting MgB2 by Specific-Heat Measurements
R. A. Fisher, F. Bouquet, N. E. Phillips +2
This paper reports specific-heat measurements on superconducting MgB2 in magnetic fields to 9 T. In zero magnetic field the data can be fitted to a two-gap model, which is a genera…
Phenomenological two-gap model for the specific heat of MgB_2
F. Bouquet, Y. Wang, R. A. Fisher +4
We show that the specific heat of the superconductor MgB_2 (MgB2) in zero field, for which significant non-BCS features have been reported, can be fitted, essentially within experi…
Dependence of the Superconducting Transition Temperature of MgB2 on Pressure to 20 GPa
S. Deemyad, J. S. Schilling, J. D. Jorgensen +1
The dependence of Tc on nearly hydrostatic pressure has been measured for an isotopically pure (11B) MgB2 sample in a helium-loaded diamond-anvil-cell to nearly 20 GPa. Tc decrease…
The reduced total isotope effect and its implications on the nature of superconductivity in MgB2
D. G. Hinks, H. Claus, J. D. Jorgensen
The recent discovery of superconductivity at ~39 K in MgB2, by Nagamatsu et al. establishes this simple binary compound as having the highest bulk superconducting transition temper…
Specific Heat of Mg ^{11}B_2
F. Bouquet, R. A. Fisher, N. E. Phillips +2
Measurements of the specific heat of Mg ^{11}B_2 (MgB2), from 1 to 50 K, in magnetic fields to 9 T, give the Debye temperature, = 1050 K, the coefficient of the normal-state el…
Lattice Properties of MgB2 versus Temperature and Pressure
J. D. Jorgensen, D. G. Hinks, S. Short
We have determined the structural properties of the superconducting compound MgB2 as a function of temperature from 11 K to 297 K and as a function of hydrostatic pressure up to 0.…
Magnetic and electronic structures of superconducting RuSrGdCuO
K. Nakamura, K. T. Park, A. J. Freeman +1
The coexistence of ferromagnetism and superconductivity in RuSrGdCuO was reported both from experiments (by Tallon et. al.) and first-principles calculations (by Picket…
Relaxation Effects in the Transition Temperature of Superconducting HgBa2CuO4+delta
S. Sadewasser, J. S. Schilling, J. L. Wagner +4
In previous studies on a number of under- and overdoped high temperature superconductors, including YBa_{2}Cu_{3}O_{7-y} and Tl_{2}Ba_{2}CuO_{6+δ}, the transition temperature T_c h…