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Giant magnetoresistance in quantum magnetic contacts

L. R. Tagirov·B. P. Vodopyanov·B. M. Garipov
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Abstract

We present calculations of quantized conductance and magnetoresistance in nanosize point contacts between two ferromagnetic metals. When conductance is open for only one conduction electrons spin-projection, the magnitude of magnetoresistance is limited by the rate of conduction electron spin-reversal processes. For the case when both spin-channels contribute to the conductance we analyze the influence of the point contact cross-section asymmetry on the giant megnetoresistance. Recent experiments on magnetoresistance of magnetic point contacts are discussed in the framework of the developed theory.

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L. R. Tagirov, B. P. Vodopyanov, B. M. Garipov. 2002-08-11. Giant magnetoresistance in quantum magnetic contacts. https://doi.org/10.1016/s0304-8853(02)01105-8

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