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arXiv · 1609.04984

Radiation induced oscillating gap states of nonequilibrium two-dimensional superconductors

Huiying Liu·Junren Shi
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Abstract

We study effects of infrared radiations on a two-dimensional BCS superconductor coupled with a normal metal substrate through a tunneling barrier. The phase transition conditions are analyzed by inspecting stability of the system against perturbations of pairing potentials. We find an oscillating gap phase with a frequency not directly related to the radiation frequency but resulting from the asymmetry of electron density of states of the system as well as the tunneling amplitude. When such a superconductor is in contact with another superconductor, it will give rise to an unusual alternating Josephson current.

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Huiying Liu, Junren Shi. 2016-10-31. Radiation induced oscillating gap states of nonequilibrium two-dimensional superconductors. https://doi.org/10.1088/0256-307x%2F35%2F6%2F067401

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