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Flux Flow Instabilities in Microstructured Amorphous Nb0.7Ge0.3 Thin Films

D. Babic·J. Bentner·C. Suergers·C. Strunk
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Abstract

We report measurements of the electric field vs. current density [E(J] characteristics in the mixed state of amorphous Nb0.7Ge0.3 microbridges. Close to the transition temperature Tc the Larkin-Ovchinnikov theory of nonlinear flux flow and the related instability describes the data quantitatively up to ~ 70% of the upper critical magnetic field Bc2 and over a wide electric field range. At lower temperatures the nonlinearities of E(J)can be described by electron heating which reduces Bc2 and leads to a second type of flux flow instability, as shown by a scaling analysis of the high-dissipation data.

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D. Babic, J. Bentner, C. Suergers, C. Strunk. 2003-07-18. Flux Flow Instabilities in Microstructured Amorphous Nb0.7Ge0.3 Thin Films. https://arxiv.org/abs/cond-mat/0307463

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