Quantum Kinetics of the Magneto Photo Galvanic Effect

TL;DR

This paper develops a quantum kinetic theory for the photogalvanic effect in noncentrosymmetric crystals, incorporating magnetic fields and polarization effects, with implications for photovoltaic materials and topological phenomena.

Contribution

It derives quasiclassical equations using the Keldysh technique that include the shift photogalvanic effect and challenges previous claims about its role in photo-Hall currents.

Findings

Explicit photogalvanic tensor formulas for polarized light and magnetic fields.

Disproves the claim that shift PGE does not contribute to photo-Hall current.

Provides a framework for analyzing PGE in topological and nanophotonic systems.

Abstract

Using the Keldysh technique, we derive a set of quasiclassical equations for Bloch electrons in noncentrosymmetric crystals upon excitation with quasimonochromatic radiation in the presence of external electrical and magnetic fields. These equations are the analog to the semiconductor-Bloch-equations for the dynamics of electrons including the photogalvanic effect (PGE) in particular the shift mechanism. The shift PGE was recently identified as showing promise for the development of new photovoltaic materials. In addition, our theory may be useful to investigate the interplay between breaking time-reversal symmetry and topological properties as well as the analysis of recent local excitation experiments in nanophotonics. Explicit results for the photogalvanic tensors are presented for linear and circular polarized light and a magnetic field. In addition, we disprove existing statements that the shift-photogalvanic effect does not contribute to the photo-Hall current.