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Multivalued dependence of the magnetoresistance on the quantized conductance in nanosize magnetic contacts

L. R. Tagirov·B. P. Vodopyanov·K. B. Efetov
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Abstract

We calculate the quantized conductance of nanosize point contacts between two ferromagnets for different mutual orientations of the magnetic moments. It is found that the magnetoresistance MR is a multivalued function of the quantized conductance at the parallel alignment of the magnetizations sigma^F. This leads us to the conclusion that experimentally observed large fluctuations of MR versus sigma^F are rather due to the conductance quantization than to measurement errors or a poor reproducibility of the results. Using the results of the calculations we are able to understand experimental data obtained by Garcia et al for MR of the magnetic nanocontacts.

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L. R. Tagirov, B. P. Vodopyanov, K. B. Efetov. 2002-07-26. Multivalued dependence of the magnetoresistance on the quantized conductance in nanosize magnetic contacts. https://doi.org/10.1103/physrevb.65.214419

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