Abstract
The magnetic second-harmonic generation (MSHG), one of nonlinear magneto-optical effects, was measured by using a Ti-sapphire laser (λ = 810 nm) combined with filters, a polarizer, an analyzer, a detector and a photon-counting apparatus. The polar plot of the azimuthal dependence of the MSHG from a [Fe(3.75ML)/Au(3.75ML)] superlattice showed a four fold symmetry pattern. A reversal of the magnetic field caused reflection of the azimuthal patterns with respect to a certain axis. Nonlinear magneto-optical Kerr rotation as large as 31.1° was observed in [Fe(1.75ML)/Au(1.75ML) for the S-polarization incidence. The magnetic contribution to the azimuthal pattern was explained by symmetry analysis, taking into account the surface non-magnetic (electric dipole), bulk non-magnetic (electric quadrupole) and surface magnetic (electric dipole) contributions.
