Spin-flip noise due to nonequilibrium spin accumulation
Citation:
Liu L, Niu J, Guo H, Wei J, Li D.L, Feng J.F, Han X.F, Coey J.M.D, Zhang X.-G, Spin-flip noise due to nonequilibrium spin accumulation, Physical Review B - Condensed Matter and Materials Physics, 93, 18, 2016, 180401-Download Item:
Abstract:
When current flows through a magnetic tunnel junction (MTJ), there is spin accumulation at the electrode-barrier interfaces if the magnetic moments of the two ferromagnetic electrodes are not aligned. Here we report that such nonequilibrium spin accumulation generates its own characteristic low frequency noise (LFN). Past work viewed the LFN in MTJs as an equilibrium effect arising from resistance fluctuations (SR) which a passively applied current (I) converts to measurable voltage fluctuations (SV=I2SR). We treat the LFN associated with spin accumulation as a nonequilibrium effect, and find that the noise power can be fitted in terms of the spin-polarized current by SIf=aIcoth(Ib)−ab, resembling the form of the shot noise for a tunnel junction, but with current now taking the role of the bias voltage, and spin-flip probability taking the role of tunneling probability.
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Grant Number
Science Foundation Ireland (SFI)
10/IN1.13006
Author's Homepage:
http://people.tcd.ie/jcoeyDescription:
PUBLISHEDExport Date: 13 January 2017
Author: COEY, JOHN
Type of material:
Journal ArticleCollections
Series/Report no:
Physical Review B - Condensed Matter and Materials Physics93
18
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Full text availableKeywords:
magnetic tunnel junction (MTJ)DOI:
http://dx.doi.org/10.1103/PhysRevB.93.180401Metadata
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