Electron and Hole Spin Splitting and Photogalvanic Effect in Quantum Wells

TL;DR

This paper develops a theoretical model for the circular photogalvanic effect in quantum wells, showing how spin splitting influences photocurrent direction and magnitude, with detailed analysis of various asymmetry sources and excitation spectra.

Contribution

It introduces a comprehensive theory linking spin-orbit interaction forms to photocurrent behavior in quantum wells, including detailed spectral calculations.

Findings

Photocurrent depends strongly on the form of spin-orbit interaction.

Different types of inversion asymmetry induce distinct photocurrent responses.

Calculated excitation spectra reveal the influence of spin splittings in conduction and valence bands.

Abstract

A theory of the circular photogalvanic effect caused by spin splitting in quantum wells is developed. Direct interband transitions between the hole and electron size-quantized subbands are considered. It is shown that the photocurrent value and direction depend strongly on the form of the spin-orbit interaction. The currents induced by structure-, bulk-, and interface-inversion asymmetry are investigated. The photocurrent excitation spectra caused by spin splittings in both conduction and valence bands are calculated.