Magnetooptical characterization of clb-type heusler compounds, pti-mni+jsbi-(x= -0.1 and 0, 0.1)

Diagonal (sxx) and off-diagonal elements of the dielectric tensor for a polished surface of a bulk sample of stoichiometric PtMnSb were obtained from the measured spectra of reflectance (R), magnetooptical Kerr rotation (0K) and ellipticity (rjK). The enhancement of 0K by annealing was found to be due mainly to the decrease in the imaginary part of exx. The magnetooptical absorption spectrum was in good agreement with that estimated from the joint density of states calculated by van der Heide et al. The spectra of exx and exy were also obtained for nonstoichiometric Pt1_A./2MnH.xSb1_Ar/2 (x=0.1 and 0.1). It was suggested that the band structure was changed by the existence of excess Mn atoms.