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Computer Simulations of Thermal Switching in Small-Grain Ferromagnets

Published online by Cambridge University Press:  10 February 2011

M. A. Novotny
Affiliation:
Supercomputer Computations Research Institute, Florida State U., Tallahassee, FL 32306-4130, USA; novotny@scri.fsu.edu; browngrg@scri.fsu.edu; rikvold@scri.fsu.edu
G. Brown
Affiliation:
Supercomputer Computations Research Institute, Florida State U., Tallahassee, FL 32306-4130, USA; novotny@scri.fsu.edu; browngrg@scri.fsu.edu; rikvold@scri.fsu.edu Center for Materials Research and Technology and Department of Physics, Florida State U., Tallahassee, FL 32306-4350
P. A. Rikvold
Affiliation:
Supercomputer Computations Research Institute, Florida State U., Tallahassee, FL 32306-4130, USA; novotny@scri.fsu.edu; browngrg@scri.fsu.edu; rikvold@scri.fsu.edu Center for Materials Research and Technology and Department of Physics, Florida State U., Tallahassee, FL 32306-4350
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Abstract

We present Monte Carlo and Langevin micromagnetic calculations to investigate thermal switching of single-domain ferromagnetic particles. For the Monte Carlo study we place particular emphasis on the probability that the magnetization does not switch by time t, Pnot(t). We find that Pnot(t) has different behaviors in different regimes of applied field, temperature, and system size, and we explain this in terms of different reversal mechanisms that dominate in the different regimes. In the micromagnetic study of an array of Ni pillars, we show that the reversal mode is an ‘outside-in’ mode starting at the perimeter of the array of pillars.

Type
Research Article
Copyright
Copyright © Materials Research Society 1998

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