Abstract A giant magneto-optical anisotropy (MOA) in a magnetic monoatomic Fe/Au multilayer structure is reported. The dependence of the off-diagonal part of the optical conductivity tensor on the angle between the magnetization and crystallographic axes is evidenced by measurements of both the polar and longitudinal Kerr effects. The microscopic origin of the MOA is elucidated on the basis of the first principles' band-structure calculations. A relationship of the MOA with the predicted strong anisotropy of Fe d orbital magnetic moment and the magnetocrystalline anisotropy is discussed.
