Micromagnetics of single and double point contact spin torque oscillators
Micromagnetics of single and double point contact spin torque oscillators
复制标题
单点和双点接触自旋力矩振荡器的微磁学
DOI：
10.1063/1.3110185
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发表时间：
2008
影响因子：
3.2
通讯作者：
J. Fidler
中科院分区：
文献类型：
--
作者：
G. Hrkac;J. Dean;A. Goncharov;S. Bance;D. Allwood;T. Schrefl;D. Suess;J. Fidler
在薄膜几何结构的自旋波的微磁模拟中，为了避免自旋波的反射，必须在计算区域的边界上应用特殊的边界条件。在本文中，我们提出了用一种抑制自旋波反射的人工粗糙表面来处理具有点接触几何结构的自旋扭矩振子。结果表明，表面粗糙度模型分散了反射自旋波，提高了信本底噪声比。通过与传统方法如延伸层体系法、变阻尼系数法和双点接触焦点法的比较，验证了该模型的有效性。表面粗糙度模型给出的解在时间上是稳定的，与实验定性一致，并且能够再现双点接触中的锁相现象。
In micromagnetic simulations of spin waves in thin film geometries special boundary conditions have to be applied at the boundary of the computational domain in order to avoid the reflection of spin waves. In this paper we proposed to use an artificially rough surface that will suppress spin wave reflections in order to treat spin torque oscillators with point contact geometry numerically. It is shown that the surface roughness model disperses the reflected spin waves and improves the signal to background noise ratio. The model is tested in comparison to conventional approaches such as extended layer systems, variable damping constant, and focal point methods for double point contacts. The surface roughness model gives solutions that are stable in time, in qualitative agreement with experiments and capable to reproduce phenomena such as phase locking in double point contacts.