Spin lifetime measurements in GaAsBi thin films

TL;DR

This study investigates spin dephasing and recombination times in GaAsBi thin films using photoluminescence and Hanle effect measurements, revealing temperature-dependent spin dynamics influenced by hole localization.

Contribution

It provides new insights into the temperature dependence of spin dephasing times and the role of hole localization in GaAsBi alloys, which was not previously characterized.

Findings

gTs decreases from 0.8 ns at 40 K to 0.1 ns at 120 K

Evidence of thermally activated effects on spin dephasing

Hole localization impacts spin dynamics below 40 K

Abstract

Photoluminescence spectroscopy and Hanle effect measurements are used to investigate carrier spin dephasing and recombination times in the semiconductor alloy GaAsBi as a function of temperature and excitation energy. Hanle effect measurements reveal the product of g-factor and effective spin dephasing time (gTs) ranges from 0.8 ns at 40 K to 0.1 ns at 120 K. The temperature dependence of gTs provides evidence for a thermally activated effect, which is attributed to hole localization at single Bi or Bi cluster sites below 40 K.