  Ultra-Light Dark Matter (ULDM) halos constituted by Ultra-Light Axions (ULAs)
generate gravitational potentials that oscillate in time. In this paper I show
these potentials interact with gravitational waves, resonantly amplifying them.
For all ULA masses considered, the resonance in the solar region is currently
negligible, while in a denser dark matter environment, which may arise in
different scenarios, it might become significant. The frequency of the
amplified gravitational wave is equal to the ULA mass in the case of first
resonance band, which represents the most efficient scenario.
