ISSN:
1090-6487
Keywords:
71.30.+h
;
72.20.Fr
;
74.50.+r
Source:
Springer Online Journal Archives 1860-2000
Topics:
Physics
Notes:
Abstract We report a study of the temperature dependence, down to 30 mK, of the magnetoresistance of Cd-Sb alloy in the insulating phase obtained by annealing the quenched metallic superconducting ( T c ≈4.5 K) phase of the alloy. Even though the sample in this state is no longer superconducting, the observed negative magnetoresistance points to single-particle tunneling in the presence of a superconducting gap in the spectrum. At magnetic fields B〈T the ratio α(T,B)=R(T,B)/R(T,B=4 T)is found to be maximum at a temperature of about 0.1 K. This behavior indicates a change of the conductivity mechanism from single-particle tunneling to incoherent two-particle tunneling as the temperature decreases.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1134/1.567295
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