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.

在平面外外场下，使用时间分辨磁光克尔测量研究了在 GaAs 衬底上外延生长的薄 Co _{2 FeAl 薄膜的磁动力学。当旋进频率被调谐到与 Co 2} FeAl/GaAs 异质结构中的相干纵向声子共振时，本征磁阻尼常数不应随外部磁场而变化，它表现出异常的巨大增加。实验结果被认为是由于在共振耦合条件下通过磁弹性效应从自旋到声学声子的强相干能量转移导致自旋的巨大能量耗散和 Co _{2中的磁阻尼大大增强}铁铝。我们的实验结果为通过磁弹性效应传播声子驱动的自旋泵浦效应提供了实验证据，这为通过相干声波进行可能的远程自旋操纵提供了另一种方法。