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A new time quantifiable Monte Carlo method in simulating magnetization reversal process

X. Z. Cheng·M. B. A. Jalil·H. K. Lee·Y. Okabe
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Abstract

We propose a new time quantifiable Monte Carlo (MC) method to simulate the thermally induced magnetization reversal for an isolated single domain particle system. The MC method involves the determination of density of states, and the use of Master equation for time evolution. We derive an analytical factor to convert MC steps into real time intervals. Unlike a previous time quantified MC method, our method is readily scalable to arbitrarily long time scales, and can be repeated for different temperatures with minimal computational effort. Based on the conversion factor, we are able to make a direct comparison between the results obtained from MC and Langevin dynamics methods, and find excellent agreement between them. An analytical formula for the magnetization reversal time is also derived, which agrees very well with both numerical Langevin and time-quantified MC results, over a large temperature range and for parallel and oblique easy axis orientations.

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X. Z. Cheng, M. B. A. Jalil, H. K. Lee, Y. Okabe. 2005-04-14. A new time quantifiable Monte Carlo method in simulating magnetization reversal process. https://doi.org/10.1103/physrevb.72.094420

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