S. Yamaguchi et al., MAGNETOOPTICAL KERR EFFECTS IN PEROVSKITE-TYPE TRANSITION-METAL OXIDES - LA1-XSRXMNO3 AND LA1-XSRXCOO3, Physical review. B, Condensed matter, 58(11), 1998, pp. 6862-6870
Magneto-optical Kerr effects have been investigated for perovskite-typ
e hole-doped oxides La1-xSrxMnO3 (0 less than or equal to x less than
or equal to 0.3) and La1-xSrxCoO3 (0 less than or equal to x less than
or equal to 0.3) in the photon energy range between 0.9 and 5.3 eV at
room temperature. In La1-xSrxMnO3, charge-transfer-type Kerr spectra
are observed for the lowest (similar to 1.2 eV) and the second-lowest(
similar to 3.5 eV) optical transitions that are likely to arise from e
lectron excitations from the O 2p to the majority-spin e(g) band and t
o the minority-spin t(2g) band, respectively. In La1-xSrxCoO3, a cryst
al-field-transition-type Kerr spectrum is observed that is assigned to
the electron excitation from the bonding t(2g) Stale to the antibondi
ng e(g) state allowed by the strong hybridization effect between Co 3d
and O 2p states. Different characters in the Hund's-rule couplings an
d covalency seem to cause such a difference in magneto-optical propert
ies between ferromagnetic Mn and Co oxides.