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arXiv · 1010.3925

Vortex instability in molybdenum-germanium superconducting films

Manlai Liang·Milind N. Kunchur
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Abstract

We studied the high driving force regime of the current-voltage transport response in the mixed state of amorphous molybdenum-germanium superconducting films to the point where the flux flow becomes unstable. The observed nonlinear response conforms with the classic Larkin-Ovchinikov (LO) picture with a quasiparticle-energy-relaxation rate dominated by the quasiparticle recombination process. The measured energy relaxation rate was found to have a magnitude and temperature dependence in agreement with theory. PACS: 74.40.Gh, 74.25.Uv, 72.15.Lh, 73.50.Gr, 73.50.Fq Keywords: fluxon, vortices, TDGL, FFF, negative differential conductivity, NDC, non-monotonic IV curve

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Manlai Liang, Milind N. Kunchur. 2010-10-19. Vortex instability in molybdenum-germanium superconducting films. https://doi.org/10.1103/physrevb.82.144517

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