We report electrical detection of the dynamical part of the spin pumping current emitted during ferromagnetic resonance (FMR) using the inverse Spin Hall Effect (ISHE). The experiment is performed on a YIG∣Pt bilayer. The choice of YIG, a magnetic insulator, ensures that no charge current flows between the two layers and only pure spin current produced by the magnetization dynamics are transferred into the adjacent strong spin-orbit Pt layer via spin pumping. To avoid measuring the parasitic eddy currents induced at the frequency of the microwave source, a resonance at half the frequency is induced using parametric excitation in the parallel geometry. Triggering this nonlinear effect allows to directly detect on a spectrum analyzer the microwave component of the ISHE voltage. Signals as large as 30 μV are measured for precession angles of a couple of degrees. This direct detection provides a novel efficient means to study magnetization dynamics on a very wide frequency range with great sensitivity.
@article{arxiv.1308.3433,
title = {Detection of the microwave spin pumping using the inverse spin Hall effect},
author = {Christian Hahn and Grégoire de Loubens and Michel Viret and Vladimir V. Naletov and J. Ben Youssef and Olivier Klein},
journal= {arXiv preprint arXiv:1308.3433},
year = {2013}
}