Probing GHz Gravitational Waves with Graviton-magnon Resonance

Abstract

A novel method for extending frequency frontier in gravitational wave observations is proposed. It is shown that gravitational waves can excite a magnon. Thus, gravitational waves can be probed by a graviton-magnon detector which measures resonance fluorescence of magnons. Searching for gravitational waves with a wave length $\lambda$ by using a ferromagnetic sample with a dimension $l$, the sensitivity of the graviton-magnon detector reaches spectral densities, around $5.4\times 10^{-22}\times (\frac{l}{\lambda /2\pi }{)}^{-2}[{\mathrm{Hz}}^{-1/2}]$ at 14 GHz and $8.6\times 10^{-21}\times (\frac{l}{\lambda /2\pi }{)}^{-2}[{\mathrm{Hz}}^{-1/2}]$ at 8.2 GHz, respectively.

Comments: 5 pages, 1 figure, minor changes