Superconducting photocurrents induced by structured electromagnetic radiation

TL;DR

This paper presents a phenomenological theory of how structured electromagnetic radiation, specifically twisted light with angular momentum, induces photocurrents and magnetic fields in superconductors, with potential experimental implications.

Contribution

It introduces a new theoretical framework describing superconducting responses to twisted light, incorporating the complex relaxation time in the Ginzburg-Landau model.

Findings

Photocurrents depend on light helicity and orbital angular momentum.

Spatial profiles of induced currents and fields are calculated.

Potential experimental setups to detect these effects are discussed.

Abstract

We develop a phenomenological theory describing the interaction of superconducting condensate with a Bessel beam of twisted light characterized by a nonzero angular momentum $m$. Starting from the time-dependent Ginzburg-Landau model with the complex relaxation time we calculate the spatial profiles of dc photoinduced currents and magnetic fields as well as the second harmonic response. The photocurrents and magnetic fileds are shown to be determined both by the helicity of light and its orbital momentum $m$. Analyzing the half-space and thin film geometries we discuss possible experimental tests aimed to probe the superconducting photocurrents and magnetic fields.