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arXiv · 1005.1280

Controlling the spin orientation of photoexcited electrons by symmetry breaking

Lan Qing·Yang Song·Hanan Dery
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Abstract

We study reflection of optically spin-oriented hot electrons as a means to probe the semiconductor crystal symmetry and its intimate relation with the spin-orbit coupling. The symmetry breaking by reflection manifests itself by tipping the net-spin vector of the photoexcited electrons out of the light propagation direction. The tipping angle and the pointing direction of the net-spin vector are set by the crystal-induced spin precession, momentum alignment and spin-momentum correlation of the initial photoexcited electron population. We examine non-magnetic semiconductor heterostructures and semiconductor/ferromagnet systems and show the unique signatures of these effects.

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Lan Qing, Yang Song, Hanan Dery. 2011-06-27. Controlling the spin orientation of photoexcited electrons by symmetry breaking. https://doi.org/10.1103/physrevlett.107.107202

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