We show that the resonant coupling of phonons and magnons can be exploited to generate spin currents at room temperature. Surface acoustic wave (SAW) pulses with a frequency of 1.55 GHz and duration of 300 ns provide coherent elastic waves in a ferromagnetic thin film/normal metal (Co/Pt) bilayer. We use the inverse spin Hall voltage in the Pt as a measure for the spin current and record its evolution as a function of time and external magnetic field magnitude and orientation. Our experiments show that a spin current is generated in the exclusive presence of a resonant elastic excitation. This establishes acoustic spin pumping as a resonant analogue to the spin Seebeck effect.
@article{arxiv.1110.1187,
title = {Spin pumping with coherent elastic waves},
author = {M. Weiler and H. Huebl and F. S. Goerg and F. D. Czeschka and R. Gross and S. T. B. Goennenwein},
journal= {arXiv preprint arXiv:1110.1187},
year = {2013}
}