  We investigate the anisotropic nature of magnetocrystalline coupling between
the crystallographic and skyrmion crystal (SKX) lattices in the chiral magnet
MnSi by magnetic field-angle resolved resonant ultrasound spectroscopy. Abrupt
changes are observed in the elastic moduli and attenuation when the magnetic
field is parallel to the [011] crystallographic direction. These observations
are interpreted in a phenomenological Ginzburg-Landau theory that identifies
switching of the SKX orientation to be the result of an anisotropic
magnetocrystalline coupling potential. Our paper sheds new light on the nature
of magnetocrystalline coupling potential relevant to future spintronic
applications.
