Volume 7, Issue 2, March 2019, Page: 55-60
Simplified Fokker-Plank Equation Treatment of Finite-temperature Spin-torque Problems
Xia Jianbai, Institute of Semiconductors, University of Chinese Academy of Sciences, Beijing, China
Wen Hongyu, Institute of Semiconductors, University of Chinese Academy of Sciences, Beijing, China
Received: Jan. 11, 2019;       Accepted: May 23, 2019;       Published: Jun. 12, 2019
DOI: 10.11648/j.ajpa.20190702.14      View  497      Downloads  88
A Legendre function expansion method is proposed to solve the simplified Fokker-Plank equation to study the dynamics of a macrospin under spin-torque-driven magnetic reversal at finite temperature. The first and second eigenvalues (λτ0)1 and (λτ0)2 as functions of I/Ic and Hk are obtained, in agreement with the previous results using the Taylor series expansion method. The Legendre function expansion method compared with the Taylor series expansion method has faster convergence properties and clear physical means. Besides, it is found that in some case, especially the second eigenvalue (λτ0)2 can become complex, that means that the probability density P not only decays with time, but also oscillates with time.
Fokker-Plank Equation, Legendre Function, Thermal Fluctuation, Magnetic Reversal
To cite this article
Xia Jianbai, Wen Hongyu, Simplified Fokker-Plank Equation Treatment of Finite-temperature Spin-torque Problems, American Journal of Physics and Applications. Vol. 7, No. 2, 2019, pp. 55-60. doi: 10.11648/j.ajpa.20190702.14
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This article is an open access article distributed under the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/) which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
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