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arXiv · 1611.02079

Current noise generated by spin imbalance in presence of spin relaxation

V. S. Khrapai·K. E. Nagaev
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Abstract

We calculate current (shot) noise in a metallic diffusive conductor generated by spin imbalance in the absence of a net electric current. This situation is modeled in an idealized three-terminal setup with two biased ferromagnetic leads (F-leads) and one normal lead (N-lead). Parallel magnetization of the F-leads gives rise in spin-imbalance and finite shot noise at the N-lead. Finite spin relaxation results in an increase of the shot noise, which depends on the ratio of the length of the conductor ($L$) and the spin relaxation length ($l_s$). For $L\gg l_s$ the shot noise increases by a factor of two and coincides with the case of the anti-parallel magnetization of the F-leads.

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V. S. Khrapai, K. E. Nagaev. 2016-11-07. Current noise generated by spin imbalance in presence of spin relaxation. https://doi.org/10.1134/s0021364017010015

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