Semiclassical dynamics and transport of the Dirac spin

Chih-Piao Chuu; Ming-Che Chang; Qian Niu

doi:10.1016/j.ssc.2009.10.039

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arXiv · 0911.4760

Semiclassical dynamics and transport of the Dirac spin

Chih-Piao Chuu·Ming-Che Chang·Qian Niu

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Abstract

A semiclassical theory of spin dynamics and transport is formulated using the Dirac electron model. This is done by constructing a wavepacket from the positive-energy electron band, and studying its structure and center of mass motion. The wavepacket has a minimal size equal to the Compton wavelength, and has self-rotation about the average spin angular momentum, which gives rise to the spin magnetic moment. Geometric gauge structure in the center of mass motion provides a natural explanation of the spin-orbit coupling and various Yafet terms. Applications of the spin-Hall and spin-Nernst effects are discussed.

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Chih-Piao Chuu, Ming-Che Chang, Qian Niu. 2009-11-25. Semiclassical dynamics and transport of the Dirac spin. https://doi.org/10.1016/j.ssc.2009.10.039

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