Effect of an interface boundary on the magnetooptical and magnetotransport properties of La_(0.67)Ca_(0.33)MnO_3/La_(0.67)Sr_(0.33)MnO_3 heterostructures

摘要

The optical, magnetooptical (Kerr effect and magnetotransmission), and magnetotransport properties of La_(2/3)Ca_(1/3)MnO_3/La_(2/3)Sr_(1/3)MnO_3 and La_(2/3)Ca_(1/3)MnO_3/SrTiO_3/La_(2/3)Sr_(1/3)MnO_3 heterostructures on SrTiO_3 substrates are studied. The contribution of the interface boundary to the magnetotransmission is typical of a material with a transitional composition. It is found that a 2-nm-thick SrTiO_3 spacer does not influence the shape and position of the magnetotransmission peak in a field normal to the surface of the heterostructure but increases the contribution of the upper layer to the magnetotransmission in the Voigt geometry and also enhances the magnetoresistance that is due to the tunneling of spin-polarized carriers through the spacer. The Kerr spectra taken of the heterostructures are typical of single-layer single-crystal films.