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Current and power spectrum in a magnetic tunnel device with an atomic size spacer

Bogdan R. Bulka
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Abstract

Current and its noise in a ferromagnetic double tunnel barrier device with a small spacer particle were studied in the framework of the sequential tunneling approach. Analytical formulae were derived for electron tunneling through the spacer particle containing only a single energy level. It was shown that Coulomb interactions of electrons with a different spin orientation lead to an increase of the tunnel magnetoresistance. Interactions can also be responsible for the negative differential resistance. A current noise study showed, which relaxation processes can enhance or reduce fluctuations leading either to a super-Poissonian or a sub-Poissonian shot noise.

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Bogdan R. Bulka. 2000-03-27. Current and power spectrum in a magnetic tunnel device with an atomic size spacer. https://doi.org/10.1103/physrevb.62.1186

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