Magnetorefractive Effect in Doped La1-xKxMnO3 Thin Films

Influence the deposition of La3+ ions by monovalent K+ ions on magnetorefractive effect on magnetoreflaction and magnetotransmission modes in the infrared range for La1-xKxMnO3 epitaxial thin-films (х=0.05, 0.10, 0.15 и 0.18) has been studied. It has been shown that the magnetorefractive effect, transversal Kerr effect and magnetoresistance reach the maximum in optimally doped films at highest Curie temperature. The good agreement between calculated in framework of magnetorefractive effect theory and experimental data takes place only for optimally doped films, with potassium concentrations of 15 % and 18 %. At the other doping levels the films become charge and magnetic inhomogeneous. Magnetic and charge homogeneity influence strongly on magnetooptical effects in films. The resonance-like lines in magnetoreflection spectra of films are connected with the shifting of reflection minimum before the phonon bands under a magnetic field has been observed.