Thermal fluctuations in antiferromagnetic nanostructures

JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS

卷:489

Article

Semenov, Yuriy G.¹  Xu, Xiniy¹  Kim, Ki Wook^1,2 

[1] North Carolina State Univ, Dept Elect & Comp Engn, Raleigh, NC 27695 USA

[2] North Carolina State Univ, Dept Phys, Raleigh, NC 27695 USA

关键词: Antiferromagnetic nano-particles;    Thermal noise;    Retention time;   

DOI  :  10.1016/j.jmmm.2019.165457

来源: Elsevier

【 摘 要 】

A theoretical model is developed that can accurately analyze the effects of thermal fluctuations in antiferromagnetic (AFM) nano-particles. The approach is based on Fourier series representation of the random effective field with cut-off frequencies of physical origin at low and high limits while satisfying the fluctuation-dissipation theorem at the same time. When coupled with the formalism of a Langevin dynamical equation, it can describe the stochastic Ned vector dynamics with the AFM parameters, circumventing the arbitrariness of the commonly used treatments in the micro-magnetic simulations. Subsequent application of the model to spontaneous Ned vector switching provides a thermal stability analysis of the AFM states. The numerical simulation shows that the AFM states are much less prone to the thermally induced accidental flips than the ferromagnetic counterparts, suggesting a longer retention time for the former.

【 授权许可】

Free