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Spin relaxation of two-dimensional electrons with a hierarchy of spin-orbit couplings

Yuan Li·You-Quan Li
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Abstract

The density matrix formalism is applied to calculate the spin-relaxation time for two-dimensional systems with a hierarchy of spin-orbit couplings, such as Rashba-type, Dresselhaus-type and so on. It is found that the spin-relaxation time can be infinite if those coupling strengths $α$, $β$, $γ_1$ and $γ_2$ satisfy either condition (i) $α=β, γ_1=0$ or (ii) $α=-β, γ_2=0$, which correspond to the vanishing Yang-Mills "magnetic" field. The effect caused by the application of an external magnetic field is also discussed. It is found that the longitudinal and in-plane spin components can possess infinite life time when the spin components, the Larmor precession frequency and the external magnetic field satisfy certain relations.

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Yuan Li, You-Quan Li. 2006-10-25. Spin relaxation of two-dimensional electrons with a hierarchy of spin-orbit couplings. https://doi.org/10.1088/0953-8984%2F19%2F34%2F346231

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