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arXiv · 1111.2681

Shot noise in magnetic tunnel junctions from first principles

Kai Liu·Ke Xia·Gerrit E. W. Bauer
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Abstract

We compute the shot noise in ballistic and disordered Fe/MgO/Fe tunnel junctions by a wave function-matching method. For tunnel barriers with no more than 5 atomic layers we find a suppression of the Fano factor as a function of the magnetic configuration. For thicker MgO barriers the shot noise is suppressed up to a threshold bias indicating the onset of resonant tunneling. We find excellent agreement with recent experiments when interface disorder is taken into account

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Kai Liu, Ke Xia, Gerrit E. W. Bauer. 2011-11-11. Shot noise in magnetic tunnel junctions from first principles. https://doi.org/10.1103/physrevb.86.020408

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