Resonant enhancement of magnetic damping driven by coherent acoustic phonons in thin Co2FeAl film epitaxied on GaAs

• 作者: Lin Song Wei Yan Hailong Wang Jianhua Zhao Xinhui Zhang
• 来源期刊: 半导体学报（英文版）
• 年，卷（期）: 2021,（3）
• 所属期刊栏目: ARTICLES
• 页码范围: 71-77
• 页数: 7页
• 语种: 英文
• DOI: 10.1088/1674-4926/42/3/032501

摘要

The magnetic dynamics of a thin Co2FeAl film epitaxially grown on GaAs substrate was investigated using the time-resolved magneto-optical Kerr measurement under an out-of-plane external field.The intrinsic magnetic damping constant,which should do not vary with the external magnetic field,exhibits an abnormal huge increase when the precession frequency is tuned to be resonant with that of the coherent longitudinal acoustic phonon in the Co2FeAl/GaAs heterostructure.The experimental finding is suggested to result from the strong coherent energy transfer from spins to acoustic phonons via magnetoelastic effect under a resonant coupling condition,which leads to a huge energy dissipation of spins and a greatly enhanced magnetic damping in Co2FeAl.Our experimental findings provide an experimental evidence of spin pumping-like effect driven by propagating acoustic phonons via magnetoelastic effect,suggesting an alternative approach to the possible long-range spin manipulation via coherent acoustic waves.