Spectral linewidth of spin-current nano-oscillators driven by nonlocal spin injection

摘要

We study experimentally the auto-oscillation characteristics of magnetic nano-oscillators driven by pure spin currents generated by nonlocal spin injection. By combining micro-focus Brillouin light scattering spectroscopy with electronic microwave spectroscopy, we are able to simultaneously perform both the spatial and the high-resolution spectral analyses of auto-oscillations induced by spin current. We find that the devices exhibit a highly coherent dynamics with the spectral line-width of a few megahertz at room temperature. This narrow linewidth can be achieved over a wide range of operational frequencies, demonstrating a significant potential of nonlocal oscillators for applications.