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arXiv · 0803.1101

Understanding spin transport from the motion in SU(2)$\times$U(1) fields

Pei-Qing Jin·You-Quan Li
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Abstract

Starting from a continuum constituted by charged tops, we formulate the classical counterpart of a previously obtained covariant continuity-like equation for the spin current. Such a formulism provides an intuitive picture to elucidate the non-conservation of the spin current and to interpret the condition for the emergence of an infinite spin relaxation time. It also facilitates the discussion on the spin precession in a one-dimensional quantum wire with Dresselhaus and Rashba spin-orbit couplings. Furthermore, we derive the diffusion equations for both the charge and spin densities and find that they couple to each other due to the Zitterbewegung.

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Pei-Qing Jin, You-Quan Li. 2008-03-07. Understanding spin transport from the motion in SU(2)$\times$U(1) fields. https://doi.org/10.1103/physrevb.77.155304

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