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arXiv · 1001.1053

Second-order nonlinear optical effects of spin currents

Jing Wang·Bang-Fen Zhu·Ren-Bao Liu
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Abstract

A pure spin current formed by opposite spins moving in opposite directions is a rank-2 axial tensor which breaks the inversion symmetry. Thus a spin current has a second-order optical susceptibility, with unique polarization-dependence determined by the symmetry properties of the current. In particular, a longitudinal spin current, in which the spin polarization directions are parallel or anti-parallel to the moving directions, being a chiral quantity, leads to a chiral sum-frequency effect. Microscopic calculations based on the eight-band model of a III-V compound semiconductor confirm the symmetry analysis and show that the susceptibility is quite measurable under realistic conditions. The second-order nonlinear optical effects may be used for in-situ and non-destructive detection of spin currents, as a standard spectroscopy tool in research of spintronics.

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Jing Wang, Bang-Fen Zhu, Ren-Bao Liu. 2010-01-26. Second-order nonlinear optical effects of spin currents. https://doi.org/10.1103/physrevlett.104.256601

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