Ultrasonic attenuation and the resistive transition in a superconducting granular lead film

M. Levy; J. Schmidt; A. Schenstrom; M. Revzen; A. Ron; B. Shapiro; C. G. Kuper

doi:10.1103/PhysRevB.34.1508

← Back to search

Ultrasonic attenuation and the resistive transition in a superconducting granular lead film

M. Levy, J. Schmidt, A. Schenstrom, M. Revzen, A. Ron, B. Shapiro, C. G. Kuper

DOI 10.1103/PhysRevB.34.1508 · Physical Review B

T1

Active bibliographic source — not scientific approval

Bibliographic access preserves source history; it does not approve extracted materials or validate reported claims. Review warnings on each occurrence separately.

Abstract

We present a model for the temperature dependence of the resistance and ultrasonic attenuation of a superconducting granular lead film. Treating the film as a network of random resistors and using percolation methods, we postulate that while the dc resistance is the resistance of an infinite network, the surface acoustic wave measures the average resistance of finite ‘‘subnetworks,’’ the sizes of which are on the order of the acoustic wavelength. The resistance of the infinite network will vanish when more than some critical fraction of the resistors in the network becomes equal to zero. However, when the resistance of the infinite network vanishes, some of the subnetworks will still have nonzero resistance. Consequently, the ultrasonic attenuation should be nonzero even when the dc resistance vanishes. This is in agreement with our experimental data.

Source-reported materials — not catalogue approval

Formula	Reported Tc (K)	Pressure (GPa)	Type
Pb Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown
Pb Archive — visibility unverified Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.	—	Pressure not reported	unknown