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arXiv · 1808.05397

{\em Zitterbewegung} in Spin-Orbit Coupled Systems and Ehrenfest's Theorem

Debabrata Sinha·Jayanta K. Bhattacharjee
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Abstract

We use Ehrenfest's theorem to provide a particularly simple derivation of the {\em zitterbewegung} in the dynamics of initial Gaussian wave packets in a two-dimensional electron gas. For initial packets which are very wide in the $y$-direction, the {\em zitterbewegung} is only in the $y$-component of the velocity. We extend our Ehrenfest theorem based calculation to the spin-orbit coupled spinor Bose-Einstein condensate (BEC) to predict that there can be {\em zitterbewegung} in the $x$-component of the velocity in this situation driven by a combination of the nonlinear interaction in the condensate and the splitting due to the spin-orbit coupling.

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Debabrata Sinha, Jayanta K. Bhattacharjee. 2018-08-16. {\em Zitterbewegung} in Spin-Orbit Coupled Systems and Ehrenfest's Theorem. https://arxiv.org/abs/1808.05397

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