Magneto-optical effect of La0.7Ca0.3MnO3 at low temperature

The magneto-optical Kerr effect of La0.7Ca0.3MnO3 at low temperature in far-infrared terahertz and mid-infrared region from 0.2 to 1.2 eV is theoretically investigated by means of the Drude model. The complex conductivity and dielectric constants are obtained. The spectra of Kerr rotation with different external magnetic fields B and temperatures T are numerically analyzed. A large Kerr rotation in mid-infrared region could be explained as the incoherent hopping motion of polarons.