Anisotropic Dzyaloshinskii-Moriya interaction in ultrathin epitaxial Au/Co/W(110)

We used Brillouin light scattering spectroscopy to independently determine the in-plane magnetocrystalline anisotropy and the Dzyaloshinskii-Moriya interaction (DMI) in out-of-plane magnetized Au/Co/W(110). We found that the DMI strength is 2--3 times larger along the bcc[1̄10] than along the bcc[001] direction. We use analytical considerations to illustrate the relationship between the crystal symmetry of the stack and the anisotropy of microscopic DMI. Such an anisotropic DMI is the first step to realize isolated elliptical skyrmions or antiskyrmions in thin-film systems with C₂ᵥ symmetry.