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Noise-induced effects in high-speed reversal of magnetic dipole

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 Added by Andrey L. Pankratov
 Publication date 2008
  fields Physics
and research's language is English




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The effect of noise on the reversal of a magnetic dipole is investigated on the basis of computer simulation of the Landau-Lifshits equation. It is demonstrated that at the reversal by the pulse with sinusoidal shape, there exists the optimal duration, which minimizes the mean reversal time (MRT) and the standard deviation (jitter). Both the MRT and the jitter significantly depend on the angle between the reversal magnetic field and the anisotropy axis. At the optimal angle the MRT can be decreased by 7 times for damping $alpha$=1 and up to 2 orders of magnitude for $alpha$=0.01, and the jitter can be decreased from 1 to 3 orders of magnitude in comparison with the uniaxial symmetry case.

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