Transient response of a nonequilibrium superconductor to pulsed injection of quasiparticles through a tunnel barrier
- 24 Downloads
We report the first direct measurements on the transient response of a nonequilibrium superconductor to high tunnel-current pulses. The sample is a Sn-I-Sn-I-Sn double-tunnel junction and the observed transient time is 20–30 nsec, depending on the samples. The calculated results based on the nonlinear Rothwarf-Taylor equation give a good fit to the experimental data for a reasonable set of parameter values. For injection strong enough to drive a film into the inhomogeneous gap state, the contribution of the negative diffusive term becomes important, suggesting the occurrence of an effective abnormal diffusion of quasiparticles. Measurements are also performed for the transient detectorI-V characteristics at a certain sampling-gate delay time. It is shown that the inhomogeneous gap state is formed within a few tens of nanoseconds for bath temperatures both below and above Tλ.
KeywordsTransient Response Transient Time Response Pulse Injector Pulse Recombination Time
Unable to display preview. Download preview PDF.
- 1.D. N. Langenberg,Low Temperature Physics—LT14, M. Krusius and M. Vuorio, eds. (North-Holland, Amsterdam, 1975), Vol. 5, p. 223.Google Scholar
- 2.A. G. Aronov and B. Z. Spivak,Fiz. Nizk. Temp. 4, 1365 (1978) [Sov. J. Low Temp. Phys. 4, 641 (1979)].Google Scholar
- 3.G. Schön,Low Temperature Physics—LT16, W. G. Clark, ed. (North-Holland, Amsterdam, 1981), Vol. 3, p. 1677.Google Scholar
- 9.R. Sobolewski, C. V. Stancampiano, G. Mourou, and D. Butler, preprint.Google Scholar
- 10.P. W. Epperlein, K. Lassmann, and W. Eisenmenger,J. Phys. (Paris)39, C6–515 (1978).Google Scholar
- 14.I. Iguchi, private communication.Google Scholar
- 21.S. Kotani, Y. Yamaki, and I. Iguchi,Physica 107B + C, 535 (1981).Google Scholar
- 23.C.-D. Wei, X.-L. Luo, and X.-F. Meng,Physica 107B + C, 539 (1981).Google Scholar