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arXiv · 1108.4831

Sub-Poissonian shot noise in CoFeB/MgO/CoFeB-based magnetic tunneling junctions

Tomonori Arakawa·Koji Sekiguchi·Shuji Nakamura·Kensaku Chida·Yoshitaka Nishihara·Daichi Chiba·Kensuke Kobayashi·Akio Fukushima·Shinji Yuasa·Teruo Ono
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Abstract

We measured the shot noise in the CoFeB/MgO/CoFeB-based magnetic tunneling junctions with a high tunneling magnetoresistance ratio (over 200% at 3 K). Although the Fano factor in the anti-parallel configuration is close to unity, it is observed to be typically 0.91\pm0.01 in the parallel configuration. It indicates the sub-Poissonian process of the electron tunneling in the parallel configuration due to the relevance of the spin-dependent coherent transport in the low bias regime.

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Tomonori Arakawa, Koji Sekiguchi, Shuji Nakamura, Kensaku Chida, Yoshitaka Nishihara, Daichi Chiba, Kensuke Kobayashi, Akio Fukushima, Shinji Yuasa, Teruo Ono. 2011-08-24. Sub-Poissonian shot noise in CoFeB/MgO/CoFeB-based magnetic tunneling junctions. https://doi.org/10.1063/1.3590921

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