Photovoltaic effect generated by spin-orbit interactions

TL;DR

This paper proposes a photovoltaic effect in spin-orbit coupled junctions where an AC electric field induces a DC current and voltage drop, enabled by broken mirror symmetry and inelastic electron processes.

Contribution

It introduces a novel photovoltaic mechanism driven by spin-orbit interactions and symmetry breaking, distinct from quantum pumping effects.

Findings

AC electric field induces DC current in spin-orbit junctions

Voltage drop is an even function of AC frequency

Effect relies on broken mirror symmetry and inelastic processes

Abstract

An AC electric field applied to a junction comprising two spin-orbit coupled weak links connecting a quantum dot to two electronic terminals is proposed to induce a DC current and to generate a voltage drop over the junction if it is a part of an open circuit. This photovoltaic effect requires a junction in which mirror reflection-symmetry is broken. Its origin lies in the different fashion inelastic processes modify the reflection of electrons from the junction back into the two terminals, which leads to uncompensated DC transport. The effect can be detected by measuring the voltage drop that is built up due to that DC current. This voltage is an even function of the frequency of the AC electric field and is {\em not} related to quantum pumping.