Depto. Física de Materiales, Facultad de Química, Universidad del País Vasco, UPV/EHU, San Sebastián 20018, Spain ; IKERBASQUE, Basque Foundation for Science, Bilbao 48011, Spain.
Depto. Física de Materiales, Facultad de Química, Universidad del País Vasco, UPV/EHU, San Sebastián 20018, Spain.
Nanoscale Res Lett. 2014 Aug 8;9(1):386. doi: 10.1186/1556-276X-9-386. eCollection 2014.
We investigate analytically and numerically nonlinear vortex spin torque oscillator dynamics in a circular magnetic nanodot induced by a spin-polarized current perpendicular to the dot plane. We use a generalized nonlinear Thiele equation including spin-torque term by Slonczewski for describing the nanosize vortex core transient and steady orbit motions and analyze nonlinear contributions to all forces in this equation. Blue shift of the nano-oscillator frequency increasing the current is explained by a combination of the exchange, magnetostatic, and Zeeman energy contributions to the frequency nonlinear coefficient. Applicability and limitations of the standard nonlinear nano-oscillator model are discussed.
我们研究了由垂直于点平面的自旋极化电流引起的圆形磁性纳米点中非线性涡旋自旋扭矩振荡器的动力学，通过 Slonczewski 的广义非线性 Thiele 方程（包括自旋扭矩项）来描述纳米级涡核瞬态和稳定轨道运动，并分析了该方程中所有力的非线性贡献。通过组合交换、静磁和塞曼能对频率非线性系数的贡献，解释了随着电流增加纳米振荡器频率蓝移的现象。讨论了标准非线性纳米振荡器模型的适用性和局限性。
