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Semiclassical theory of spin-polarized shot noise in mesoscopic diffusive conductors

M. Zareyan·W. Belzig
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Abstract

We study fluctuations of spin-polarized currents in a three-terminal spin-valve system consisting of a diffusive normal metal wire connected by tunnel junctions to three ferromagnetic terminals. Based on a spin-dependent Boltzmann-Langevin equation, we develop a semiclassical theory of charge and spin currents and the correlations of the currents fluctuations. In the three terminal system, we show that current fluctuations are strongly affected by the spin-flip scattering in the normal metal and the spin polarizations of the terminals, which may point in different directions. We analyze the dependence of the shot noise and the cross-correlations on the spin-flip scattering rate in the full range of the spin polarizations and for different magnetic configurations. Our result demonstrate that noise measurements in multi-terminal devices allow to determine the spin-flip scattering rate by changing the polarizations of ferromagnetic terminals.

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M. Zareyan, W. Belzig. 2004-09-07. Semiclassical theory of spin-polarized shot noise in mesoscopic diffusive conductors. https://doi.org/10.1103/physrevb.71.184403

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