Optical, magneto-optical and transport properties of La1-xSrxCoO3 (x=0.15;0.25;0.35) films: spin-state transition effects

Optical absorption spectra, transverse Kerr effect, resistivity and magnetoresistance of polycrystalline films La1-xSrxCoO3 (x=0.15;0.25;0.35) are studied. The temperature dependences of optical and magneto-optical properties were found to have specific features which can be caused by changes in spin state of Co3+ ions. The results obtained support the phase separation scenario in doped cobaltates. Magnetic interaction between different phases is controlled by the number of Co3+ (intermediate-spin state, S=1) ions in the orbital ordered state