摘要
In the field of ultrafast magnetism,i.e.,subpicosecond or femtosecond time scales,the dynamics of magnetization can be described by the inertial Landau-Lifhitz-Gilbert equation.In terms of this equation,the intrinsic characteristics are investigated in detail for the theoretical limit of the magnetization reversal field.We can find that there is a critical value for the inertia parameterτ_(c),which is affected by the damping and anisotropy parameter of the system.When the inertial parameter factorτ<τ_(c),the limit value of the magnetization reversal field under the ultrafast magnetic mechanism is smaller than that of the fast magnetic mechanism.Whenτ>τ_(c),the limit value of the magnetization reversal field will be larger than the limit value under the fast magnetic mechanism.Moreover,it is important to point out that the limit value of the magnetization reversal field under the ultrafast magnetic mechanism decreases with the increasing inertial factor,asτ<τ_(c)/2,which increases with inertial factorτasτ>τ_(c)/2.Finally,with the joint action of damping and anisotropy,compared with fast magnetism,we find that the limit value of the magnetization reversal field has rich variation characteristics,i.e.,there is not only a linear and proportional relationship,but also an inverse relationship,which is very significant for the study of ultrafast magnetism.
作者
南雪萌
屈川
贺鹏斌
李再东
Xue-Meng Nan;Chuan Qu;Peng-Bin He;Zai-Dong Li(Tianjin Key Laboratory of Quantum Optics and Intelligent Photonics,School of Science,Tianjin University of Technology,Tianjin 300384,China;School of Physics and Electronics,Hunan University,Changsha 410082,China)
基金
Project supported by the National Natural Science Foundation of China (Grant No.61774001)
the Program of State Key Laboratory of Quantum Optics and Quantum Optics Devices,Shanxi University,China (Grant No.KF202203)
the NSF of Changsha City (Grant No.kq2208008)
the NSF of Hunan Province (Grant No.2023JJ30116)。
