Gd-Coアモルファス薄膜の磁気光学カー効果

Abstract

The magneto-optical Kerr effect of Gd-Co films prepared by rf magnetron sputtering is investigated for films with Gd concentration from about 10% to 50% within a wavelength range of 400&acd;1000[nm]. The Kerr rotation θ_K is well approximatd by a formura θ_K=C_<Co>|M_<Co>|+C_<Gd>|M_<Gd>| within a compositional range studied, where C_<Co> and C_<Gd> are Kerr rotation coefficients depending only on the wavelength and M_<Co> and M_<Gd> are subnetwork magnetizations of Co and Gd, rspectively. The spectra for C_<Co> and C_<Gd> are determind, which depend only slightly on the wavelength with values of about -0.3 [deg/T] for C_<Co> and -0.045 [deg/T] for C_<Gd> at 600 [nm]. It is also found that the magneticmoment of Co atom in the Gd-Co alloy decreases very slowly with increasing Gd concentration, the fact which is far different from the cases of other RE-Co films of RE=La, Ce, Pr, Nd, Sm, Tb, Dy, Ho, Er, and Tm.