Interferometric detection of spin-polarized transport in the depletion layer of a metal-GaAs Schottky barrier

TL;DR

This paper demonstrates an interferometric method using Kerr rotation to detect and analyze spin-polarized electron transport dynamics within the depletion layer of a metal-GaAs Schottky barrier.

Contribution

It introduces a novel interferometric technique to measure spin-polarized electron dynamics in the depletion layer of a Schottky barrier.

Findings

Observation of fast oscillations in Kerr rotation signals

Detection of electron transport dynamics in depletion layer

Method for measuring charge carrier dynamics

Abstract

It is shown that the Kerr rotation of spin-polarized electrons is modulated by the distance of the electrons from the sample surface. Time-resolved Kerr rotation of optically-excited spin-polarized electrons in the depletion layer of n-doped GaAs displays fast oscillations that originate from an interference between the light reflected from the semiconductor surface and from the front of the electron distribution moving into the semiconductor. Using this effect, the dynamics of the photogenerated charge carriers in the depletion layer of the biased Schottky barrier is measured.