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arXiv · 0906.4256

Inhomogeneous state in non-equilibrium superconductor/normal metal tunnel structures: a LOFF-like phase for non-magnetic systems

A. Moor·A. F. Volkov·K. B. Efetov
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Abstract

We analyze non-equilibrium states in a tunnel superconductor-normal metal (NSN) structure in the presence of a tunnel current $I$. We use an approximation of an effective temperature $T$ and calculate the current-voltage I-V characteristics. It is shown that the I-V dependence may have an S-shaped form. We determine nonuniform current $I(x)$ and temperature $T(x)$ distributions that arise as a result of instability of the uniform state with negative differential conductance ($dI/dV<0$). We discuss an analogy with equilibrium superconductors with an exchange field in which nonuniform states predicted by Larkin-Ovchinnikov and Fulde-Ferrel are possible.

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A. Moor, A. F. Volkov, K. B. Efetov. 2009-06-23. Inhomogeneous state in non-equilibrium superconductor/normal metal tunnel structures: a LOFF-like phase for non-magnetic systems. https://doi.org/10.1103/physrevb.80.054516

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