Spin splitting of X-related donor impurity states in an AlAs barrier

TL;DR

This study employs magnetotunneling spectroscopy to measure the spin splitting of X-related Si-donor impurity states in an AlAs barrier, revealing an effective Zeeman factor and anisotropic electron wave functions.

Contribution

It provides the first direct measurement of spin splitting and Zeeman factors for X-related donor impurities in AlAs barriers using magnetotunneling spectroscopy.

Findings

Effective Zeeman spin splitting factor g_I = 2.2 ± 0.1.

Electron wave function is anisotropic in the growth plane.

First direct measurement of spin splitting in this system.

Abstract

We use magnetotunneling spectroscopy to observe the spin splitting of the ground state of an X-valley-related Si-donor impurity in an AlAs barrier. We determine the absolute magnitude of the effective Zeeman spin splitting factors of the impurity ground state to be g$_{I}$= 2.2 $\pm $ 0.1. We also investigate the spatial form of the electron wave function of the donor ground state, which is anisotropic in the growth plane.