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arXiv · 0906.1581

Pure spin-current generated by reflection at a normal metal/2DEG interface

Jacob Linder·Takehito Yokoyama·Asle Sudbø
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Abstract

The concept of a spin-current is a useful tool in understanding spin-transport in hybrid systems, but its very definition is problematic in systems where spin-orbit coupling effects are strong. In the absence of spin-dependent scattering, the spin-current remains well-defined. We here propose a method for generating pure spin-currents in a normal metal where the spin-current consequently does not suffer from the aforementioned problems pertaining to its very definition or spin-relaxation processes. More specifically, we show how an unpolarized incident charge-current can induce a pure transverse spin-current by means of scattering at a normal metal/2DEG interface. This occurs for both Rashba and Dresselhaus spin-orbit coupling. An experimental setup for observation of this effect is proposed.

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Jacob Linder, Takehito Yokoyama, Asle Sudbø. 2010-01-22. Pure spin-current generated by reflection at a normal metal/2DEG interface. https://doi.org/10.1103/physrevb.81.075312

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