Thermal electron spin flip in quantum dots

TL;DR

This paper investigates the thermally induced spin flip of an electron in quantum dots, driven by the interplay of magnetic and hyperfine interactions, with predictions relevant for experimental quantum dot systems.

Contribution

It introduces a minimal model explaining the thermal spin flip mechanism and analyzes its dependence on magnetic field, nuclear spins, and Zeeman energy ratios.

Findings

Identifies the key parameters influencing the spin flip

Predicts the temperature at which the spin flip occurs in quantum dots

Demonstrates applicability to III-V heterostructure quantum dots

Abstract

We study a thermally induced spin flip of an electron spin located in a semiconductor quantum dot. This interesting effect arises from an intriguing interplay between the Zeeman coupling to an external magnetic field and the hyperfine interaction with the surrounding nuclear spins. By considering a minimal model, we explain the main mechanism driving this spin flip and analyze its dependence on the strength of the external magnetic field, the number of nuclear spins and the ratio of the electron and nuclear Zeeman energies, respectively. Finally we show, that this minimal model can be applied to experimentally relevant QDs in III-V heterostructures, where we explicitly predict the temperature at which the spin flip occurs.