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arXiv · 1205.5956

Electron spin relaxation in GaAs$_{1-x}$Bi$_x$: Effects of spin-orbit tuning by Bi incorporation

H. Tong·X. Marie·M. W. Wu
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Abstract

The electron spin relaxation in $n$-type and intrinsic GaAs$_{1-x}$Bi$_x$ with Bi composition $0\le x \le 0.1$ is investigated from the microscopic kinetic spin Bloch equation approach. The incorporation of Bi is shown to markedly decrease the spin relaxation time as a consequence of the modification of the spin-orbit interaction. We demonstrate that the density and temperature dependences of spin relaxation time in GaAs$_{1-x}$Bi$_x$ resemble the ones in GaAs. Meanwhile, the Bir-Aronov-Pikus mechanism is found to be negligible compared to the D'yakonov-Perel' mechanism in intrinsic sample. Due to the absence of direct measurement of the electron effective mass in the whole compositional range under investigation, we further explore the effect of a possible variation of electron effective mass on the electron spin relaxation.

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H. Tong, X. Marie, M. W. Wu. 2012-05-27. Electron spin relaxation in GaAs$_{1-x}$Bi$_x$: Effects of spin-orbit tuning by Bi incorporation. https://doi.org/10.1063/1.4752424

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