Probing GHz gravitational waves with graviton–magnon resonance

Abstract

Abstract A novel method for extending the 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 $$\lambda $$ λ by using a ferromagnetic sample with a dimension l, the sensitivity of the graviton–magnon detector reaches spectral densities, around $$5.4 \times 10^{-22} \times (\frac{l}{\lambda /2\pi })^{-2} \ [\mathrm{Hz}^{-1/2}]$$ 5.4×10-22×(lλ/2π)-2[Hz-1/2] at 14 GHz and $$8.6 \times 10^{-21} \times (\frac{l}{\lambda /2\pi })^{-2} \ [\mathrm{Hz}^{-1/2}]$$ 8.6×10-21×(lλ/2π)-2[Hz-1/2] at 8.2 GHz, respectively.