Department of Physics, Norwegian University of Science and Technology, NO-7491 Trondheim, Norway.
Phys Rev Lett. 2013 Aug 30;111(9):097602. doi: 10.1103/PhysRevLett.111.097602. Epub 2013 Aug 27.
Precessing magnetization in a thin-film magnetic insulator pumps spins into adjacent metals; however, this phenomenon is not quantitatively understood. We present a theory for the dependence of spin pumping on the transverse mode number and in-plane wave vector. For long-wavelength spin waves, the enhanced Gilbert damping for the transverse mode volume waves is twice that of the macrospin mode, and for surface modes, the enhancement can be ten or more times stronger. Spin pumping is negligible for short-wavelength exchange spin waves. We corroborate our analytical theory with numerical calculations in agreement with recent experimental results.
在薄膜磁性绝缘体中，进动磁化将自旋注入相邻金属中；然而，这一现象尚未得到定量理解。我们提出了一种关于自旋泵浦与横向模式数和平面波矢依赖关系的理论。对于长波长自旋波，横向模式体波的增强 Gilbert 阻尼是宏观模式的两倍，而对于表面模式，增强幅度可以大十倍甚至更多。对于短波长交换自旋波，自旋泵浦可以忽略不计。我们通过数值计算与最近的实验结果相吻合，验证了我们的分析理论。
