  For the realization of magnonic devices, spin-wave dispersions need to be
identified. Recently, the time-resolved pump-probe imaging method combined with
the Fourier transform was demonstrated for obtaining the dispersions in the
lower-wavenumber regime. However, the measurement takes a long time when the
sampling rate is sufficiently high. Here, we demonstrated the fast acquisition
of spin-wave dispersions by using the compressed sensing technique. Further, we
quantitatively evaluated the consistency of the results. Our results can be
applied to other various pump-probe measurements, such as observations based on
the electro-optical effects.
