Upper critical field of disordered NbNi alloys
Abstract
The critical fields for disordered Nb-Ni alloys are measured in the concentration region from 40 to 60 at% Nb down to temperatures below 0.1 Tc. For these alloys Tc varies by a factor of 8 while the density of states, calculated from the slope of the critical field close to Tc, is about 1 (eV atom) -1 independent of concentration. The critical fields are enhanced over the maximum value consistent with the Werthamer-Helfand-Hohenberg theory. It is suggested that weak localization effects contribute to the enhanced critical field of Nb 40Ni 60.
- Publication:
-
Physics Letters A
- Pub Date:
- February 1987
- DOI:
- 10.1016/0375-9601(87)90219-2
- Bibcode:
- 1987PhLA..120..251R