Enhancement of magneto-optical properties of the one-dimensional magnetic photonic crystals of a Co2MnSi film

Abstract

The magnetic and the magneto-optical properties of one-dimensional magnetic photonic crystals(1-D MPCs) produced by using femtosecond-laser-induced crystallization of amorphous CO2MnSi films were elucidated. The amorphous CO2MnSi films were fabricated on glass substrate at room temperature by using rf magnetron sputtering. A grating-like periodic structure was obtained by using two-beam interference of the laser pulses. The atomic-force-microscopy and the transmission-electron-microscopy results showed regularly-spaced alternating lines with a periodicity of 2 pm. Magnetic-force-microscopy revealed periodic patterns of magnetic domains in the grating. The Kerr hysteresis loops of the sample were measured via the longitudinal magneto-optical Kerr effect by using a magneto-optical microscope. The enhanced magneto-optical properties of films were observed in the first-order diffraction beam. The films with a spatially periodic magnetic structure were found to be relatively easily fabricated by selectively crystallizing a paramagnetic CO2MnSi amorphous film, which crystallized into a ferromagnetic phase upon illuminating it with a sufficiently intense laser light.