La_n-nxCa_1+nxMn_nO_3n+1薄膜の磁気的·電気的性質

抄録

The magnetic and electrical properties of two-dimensional epitaxial a-axis La_n-nxCa_1+nxMn_nO_3n+1 (n=2, 3; x=0.3) films and three-dimensional La_1-xCa_xMnO₃ (x=0.3) film were studied. Various systematic changes in the properties were observed as n (the number of MnO₂ layers) was reduced. These included a decrease in the resistivity peak temperature (T_ρ^max), and enhancement of the magnetoresistance near T_ρ^max and the characteristic low-temperature magnetoresistance whose field dependence has a hysteresis curve. It is concluded that the changes result from a decrease of the transfer (t^c_ij) along the c-axis of the crystal and the effect of spin fluctuation between MnO₂ layers.