Perpendicular magnetic anisotropy and magneto-optical Kerr effect of MnSbAg alloy films with NiAs structure

Crystal structures and magneto-optical properties of (MnSb)(100-y)Ag-y (2.1 less than or equal to y less than or equal to 10.3) alloy films prepared by RF magnetron sputtering have been studied by a X-ray diffractometer, a vibrating sample magnetometer and a Kerr loop tracer. The crystal structure of the Mn47.4Sb47.5Ag5.1 alloy film annealed at 300 degrees C is a NiAs-type with hcp. The c-axis orientation is normal to the film plane by annealing at 300 degrees C for 7 hours. The saturation magnetization of the films shows the maximum at y=5.1 and decreases with the increase of y. The perpendicular anisotropy constants of the film annealed at 300 degrees C for 7 hours are K-1 = 8.7X10(4) erg/ cm(3) and K-2 = 4.9X10(5) erg/cm(3). The Kerr rotation angle of the film decreases with decreasing incident wavelength within the range of 700 less than or equal to lambda less than or equal to 1000 nm. The polar Kerr rotation angles of 0.2 degrees(lambda=700 nm) and 0.97 degrees(lambda=1000 nm) have been obtained from the film annealed at 300 degrees C for 7 hours.