Ni-Zr amorphous alloys: Low temperature specific heat and superconductivity

• Published in: Solid state communications Vol. 46; no. 1; pp. 37 - 40
• Main Authors: Onn, David G., Wang, L.Q., Obi, Y., Fukamichi, K.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.01.1983; Elsevier
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Materials science; Metals, alloys and compounds (a15, 001c15, laves phases, chevrel phases, borocarbides, etc.); Metals, semimetals and alloys; Occurrence, potential candidates; Physics; Specific materials; Superconducting materials (excluding high-tc compounds); Superconductivity; Debye temperature; Specific heat; Density of states; Fermi level; Superconduction transition; Very low temperature; Amorphous alloy; Chemical composition; Superconducting transition; Low temperature
• ISSN: 0038-1098; 1879-2766
• DOI: 10.1016/0038-1098(83)90025-X

The specific heat (C p) of the amorphous alloys Ni 100-xZr x for x = 75, 65, 55 and 35 was measured from 0.8K to 40K and the composition trends of the transition temperature T c, the enhanced density of states at the Fermi level N γ( F) and the Debye temperatures θ D(0), θ D(T) established. For the three superconducting compositions ( x=75, 65, 55) N γ(E F increases rapidly with increasing [Zr] in agreement with the trend in amorphous Cu-Zr alloys. However, for the Zr-Ni alloys the bare density of states N 0(E F) = N γ(E F) (1 + λ p) increases strongly with [Zr] in contrast to the Zr-Cu alloys where it is reported to be almost constant. We conclude that for the Ni-Zr alloys the electron-ion matrix element <I 2> decreases with increasing [Zr]. Other results are related to recent photoemission studies of these alloys.