Charge-imbalance relaxation in the presence of a pair-breaking supercurrent in dirty, superconducting Al films

Journal Article · Sun Feb 01 00:00:00 EST 1981 · Phys. Rev. B: Condens. Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.23.1100· OSTI ID:6686644

Lemberger, T R; Clarke, J

The charge-imbalance relaxation rate, 1/F*tau/sub Q/*, has been measured in dirty Al films in the presence of an applied supercurrent for 0.7< or approx. =T/T/sub c/< or approx. =0.91. The supercurrent I/sub s/ induces an anisotropic energy gap, and hence allows elastic scattering to relax the charge imbalance. The effect of a supercurrent is equivalent to that of magnetic impurities, with a pair-breaking rate tau/sup -1//sub s/=1/2D(p/sub s//h)/sup 2/, where D is the electron diffusion constant and p/sub s/ is the momentum of a Cooper pair. The measured relaxation time, F*tau/sub Q/*, is found to depend on I/sub s/ through the relation, F*tau/sub Q/*(I/sub s/)=F*tau/sub Q/*(O)/(1+bI/sup 2//sub s/)/sup 1/2/, where b is a function of T/T/sub c/. The measured temperature dependence of b is consistent with previous measurements of 1/F*tau/sub Q/* in AlEr films, in which the Er is a pair-breaking magnetic impurity, and with the Schmid-Schoen theory. The measured magnitude of b is in good agreement with the value expected from measured sample parameters. As with the data on AlEr, the measured value of b is not consistent with results based on a numerical solution of the Boltzmann equation.

• Research Organization: Department of Physics, University of California, Berkeley, California 94720
• OSTI ID: 6686644
• Journal Information: Phys. Rev. B: Condens. Matter; (United States), Vol. 23:3
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALUMINIUM
SUPERCONDUCTIVITY
BOLTZMANN EQUATION
COOPER PAIRS
ENERGY GAP
NUMERICAL SOLUTION
RELAXATION TIME
SUPERCONDUCTING FILMS
TEMPERATURE DEPENDENCE
DIFFERENTIAL EQUATIONS
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELEMENTS
EQUATIONS
FILMS
METALS
PHYSICAL PROPERTIES
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