LAUSR

We have studied the magnetism of a cobalt ultrathin film deposited on different two-dimensional (2D) materials, namely graphene, h-BN, and ${\mathrm{WSe}}_{2}$ by the Brillouin light scattering technique. The studied samples are prepared by a pick-up method of large flakes deposited on ${\mathrm{SiO}}_{2}$ and the subsequent physical vapor deposition of metal layers, in a similar way to what is done to make spintronic devices out of such materials. Compared to the reference layer $(\mathrm{Co}/{\mathrm{SiO}}_{2})$, the perpendicular magnetic anisotropy is enhanced in the Co/2D systems, although less than what could be expected on single crystal samples. This result is quantitatively discussed by comparison with ab initio calculations in the case of the Co/graphene interface. We also measure an increase of the magnetic damping and a small Dzyaloshinskii-Moriya interaction in such samples which are discussed with respect to the recent literature.