Temperature dependence of the nonequilibrium-field penetration depth in a superconductor

Measurements are reported on the temperature dependence of the step structure in the current--voltage curves for long narrow tin films. Measurements have been made of the temperature dependence of the penetration depth, for nonequilibrium longitudinal electric fields, which defines the quasinormal N region in the S--N current stratification. It is shown that inelastic and elastic collision mechanisms are important, and the predominant one is determined by the difference between the actual temperature T and the critical temperature T/sub c/. An expression is derived that describes closely the observed dependence of delta/sub E/ on the temperature and the specimen parameters. The inelastic relaxation time is estimated as 8x10/sup -/10 sec.