Tunneling Anisotropic Spin Polarization in lateral (Ga,Mn)As/GaAs spin Esaki diode devices

TL;DR

This paper demonstrates anisotropic spin polarization in lateral (Ga,Mn)As/GaAs Esaki diode devices, showing how spin tunneling efficiency varies with crystallographic orientation, revealing significant in-plane and out-of-plane anisotropies.

Contribution

It introduces a novel all-electrical spin injection device demonstrating anisotropic spin polarization dependent on crystallographic orientation.

Findings

Observed 8% in-plane anisotropy of spin polarization.

Measured 25% anisotropy between in-plane and out-of-plane spins.

Confirmed dependence of spin tunneling efficiency on crystallographic direction.

Abstract

We report here on anisotropy of spin polarization obtained in lateral all-semiconductor all-electrical spin injection devices, employing $p^{+}-$(Ga,Mn)As/$n^{+}-$GaAs Esaki diode structures as spin aligning contacts, resulting from the dependence of the efficiency of spin tunneling on the orientation of spins with respect to different crystallographic directions. We observed an in-plane anisotropy of $~8%$ in case of spins oriented either along $[1\bar{1}0]$ or $[110]$ directions and $~25%$ anisotropy between in-plane and perpendicular-to-plane orientation of spins.