Fig. 2.

Magnetic and transport characterization of the LSMO/SIO superlattice. (A) Dependence of MA on SIO thickness (m) in the superlattice series SL3m. MA is defined as the difference of remnant moment M_R between two crystallographic directions normalized by the saturation moment M_S ($\left(M_R\left[100\right]-M_R\left[110\right]\right)/M_S$). The positive sign corresponds to the $\langle 100\rangle$ easy axis whereas the negative sign indicates a $\pi /4$ shift to $\langle 110\rangle$. The purple dot shows the anisotropy of LSMO thin film. Magnetic easy axis is shown by the arrow in the oxygen octahedral for the series of superlattices. Error bars are derived from measurements on multiple samples. (B) Magnetic hysteresis loops of an SL31 superlattice with magnetic field H in [100] (blue), [110] (red), and [010] (black) crystallographic orientation. (Inset) Plot of magnetic hysteresis loops of LSMO (20-nm) thin film on STO as a comparison. Magnetization is averaged by LSMO thickness in this study. (C) Schematic and polar plots of in-plane AMR. The current is along the [100] direction and the magnetic field (1 T) is rotated within the film plane. The polar plots show a phase shift of π/4 between SL33 and SL310, consistent with the thickness evolution of MA in A.