Spin lifetime measurements in GaAsBi thin films

Brennan Pursley; M. Luengo-Kovac; G. Vardar; R. S. Goldman; V. Sih

doi:10.1063/1.4781415

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arXiv · 1211.2711

Spin lifetime measurements in GaAsBi thin films

Brennan Pursley·M. Luengo-Kovac·G. Vardar·R. S. Goldman·V. Sih

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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.

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Brennan Pursley, M. Luengo-Kovac, G. Vardar, R. S. Goldman, V. Sih. 2013-01-04. Spin lifetime measurements in GaAsBi thin films. https://doi.org/10.1063/1.4781415

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