Vertex corrections to nonlinear photoinduced currents in 2D superconductors

Abstract

The emergence of a rectified steady-state supercurrent as a response to the photoexcited current of the quasiparticles constitutes the concept of a superconducting photodiode. This phenomenon occurs in a two-dimensional thin superconducting film with a built-in DC supercurrent that is exposed to a circularly polarized external electromagnetic field. The flow of a Cooper-pair condensate, resulting as a second-order photo-response in a direction transverse to the initially built-in supercurrent, represents a superconducting counterpart to the photogalvanic effect. In this paper, we examine the photodiode supercurrent by restoring gauge invariance within the mean-field BCS framework. To achieve this, we derive an impurity-sensitive BCS-interaction-induced correction to the vertex function by performing self-consistent calculations within the Keldysh Green's function technique. The resulting photodiode current can be utilized for spectroscopic analysis of typical relaxation times in superconducting films.

References in corpus (15)

• Nonlinear Hall Effects
• A phenomenological theory of superconductor diodes
• Universal Josephson diode effect
• Theory of the supercurrent diode effect in Rashba superconductors with arbitrary disorder
• General theory of Josephson Diodes
• Superconducting spintronic tunnel diode
• Current-enabled optical conductivity of superconductors
• Quantum phase transition of correlated iron-based superconductivity in LiFe${}_{1-x}$Co${}_x$As
• Optical Conductivity From Pair Density Waves
• Supercurrent induced resonant optical response
• Nonlinear microwave response of clean superconducting films
• Photoinduced Anomalous Supercurrent Hall Effect
• Giant microwave absorption in s- and d- wave superconductors
• Second-order optical response of superconductors induced by supercurrent injection
• Proposal for Superconducting Photodiode