Semiclassical dynamics and transport of the Dirac spin
نویسندگان
چکیده
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 ofmassmotion. Thewavepacket has aminimal size equal to the Comptonwavelength, 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. © 2009 Elsevier Ltd. All rights reserved.
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