Structure and magnetoresistance of La0.67Ca0.33MnO3 films grown coherently on (001)NdGaO3

40- to 120-nm-thick (001)La0.67Ca0.33MnO3 films grown through laser evaporation on (001)NdGaO3 were studied. The lattice parameters of the La0.67Ca0.33MnO3 films measured in the substrate plane (a(parallel toparallel to) = 3.851 Angstrom) and along the normal to its surface (a(perpendicular to) = 3.850 Angstrom) practically coincided with that of the pseudocubic neodymium gallate. The unit-cell volume of the La0.67Ca0.33MnO3 film was slightly smaller than that of stoichiometric bulk samples. The position of the maximum in the temperature dependence of electrical resistivity did not depend on the thickness of the La0.67Ca0.33MnO3 film. The negative magnetoresistance (MR approximate to -0.25, H = 0.4 T) of La0.67Ca0.33MnO3 films reached a maximum at 239-244 K. (C) 2003 MAIK "Nauka / Interperiodica".