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arXiv · 1604.08422

Nonlinear Transport in a Two Dimensional Holographic Superconductor

Hua Bi Zeng·Yu Tian·Zhe Yong Fan·Chiang-Mei Chen
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Abstract

The problem of nonlinear transport in a two dimensional superconductor with an applied oscillating electric field is solved by the holographic method. The complex conductivity can be computed from the dynamics of the current for both near- and non-equilibrium regimes. The limit of weak electric field corresponds to the near equilibrium superconducting regime, where the charge response is linear and the conductivity develops a gap determined by the condensate. A larger electric field drives the system into a superconducting non-equilibrium steady state, where the nonlinear conductivity is quadratic with respect to the electric field. Keeping increasing the amplitude of applied electric field results in a far-from-equilibrium non-superconducting steady state with a universal linear conductivity of one. In lower temperature regime we also find chaotic behavior of superconducting gap, which results in a non-monotonic field dependent nonlinear conductivity.

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Hua Bi Zeng, Yu Tian, Zhe Yong Fan, Chiang-Mei Chen. 2016-04-28. Nonlinear Transport in a Two Dimensional Holographic Superconductor. https://doi.org/10.1103/physrevd.93.121901

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