Abrupt barrier contribution to the electron spin splitting in asymmetric coupled double quantum wells

TL;DR

This paper investigates how abrupt interfaces in asymmetric coupled double quantum wells influence electron spin-splitting, using an advanced modeling approach to predict observable effects in photoluminescence excitation.

Contribution

An improved 8x8 Transfer Matrix Approach that accounts for abrupt interface contributions and external fields in double quantum wells.

Findings

Electron spin-splitting variations cause notable features in the density of states.

Density of states variations are detectable via photoluminescence excitation.

The model predicts observable effects of interface contributions on electron spin properties.

Abstract

We have studied the behavior of the electronic energy spin-splitting of InGaAs-InAlAs based double quantum wells (narrow gap structures) under in-plane magnetic and transverse electric fields. We have developed an improved 8x8 version of the Transfer Matrix Approach that consider contributions from abrupt interfaces and external fields when tunneling through central barrier exists. We have included the Land\'e g-factor dependence on the external applied field. Also, we have calculated electron density of states and photoluminescence excitation. Variations of the electron spin-splitting energy lead to marked peculiarities in the density of states. Because the density of states is directly related to photoluminescence excitation, these peculiarities are observable by this technique.