Determination of spin polarization in InAs/GaAs self-assembled quantum dots

TL;DR

This paper investigates the spin polarization of electrons in InAs/GaAs quantum dots using magneto-capacitance spectroscopy, revealing full polarization above 10 T and analyzing angular dependence with g-tensor anisotropy.

Contribution

It introduces a statistical method to infer spin polarization from addition energies and includes the angular dependence considering g-tensor anisotropy.

Findings

Full spin polarization above 10 T at 2.8 K

Spin polarization depends on magnetic field orientation and strength

Method to determine spin polarization from addition energies

Abstract

The spin polarization of electrons trapped in InAs self-assembled quantum dot ensembles is investigated. A statistical approach for the population of the spin levels allows one to infer the spin polarization from the measure values of the addition energies. From the magneto-capacitance spectroscopy data, the authors found a fully polarized ensemble of electronic spins above 10 T when $\mathbf{B}\parallel[001]$ and at 2.8 K. Finally, by including the g-tensor anisotropy the angular dependence of spin polarization with the magnetic field $\mathbf{B}$ orientation and strength could be determined.