Model of circular polarization dependence on Mn delta-layer position in LED heterostructures with InGaAs/GaAs quantum well

TL;DR

This paper proposes a simple model explaining how the position of Mn delta-layers in InGaAs/GaAs quantum well LED heterostructures influences circular polarization, aligning well with recent experimental findings.

Contribution

The model highlights the impact of position-dependent exchange interaction and structural factors on polarization, providing new insights into spin-dependent effects in these heterostructures.

Findings

Model accurately explains experimental polarization dependence

Position of Mn delta-layer critically affects hole level splitting

Structural imperfections influence polarization behavior

Abstract

A simple model of circular polarization dependence on Mn delta-layer position in LED heterostructures with InGaAs/GaAs quantum well is proposed, being able to explain quite accurately recent fascinating experimental results [S.V. Zaitsev, et al., Physica E (2009), doi:10.1016/j.physe.2008.11.003]. The model emphasizes the role of position-dependent exchange interaction between injected holes and Mn spins which significantly affects the hole level splitting in a magnetic field, leading to strong variations of polarization dependence. The role of effective temperature corresponding to the injected hole energy and the broadening caused by the geometrical structure imperfections is also discussed.