Magnetic Properties at Surface Boundary of a Half-Metallic FerromagnetLa0.7Sr0.3MnO3

The surface-boundary magnetization $\left(M_{\mathrm{SB}}\right)$ for a manganese perovskite ${\mathrm{La}}_{0.7}{\mathrm{Sr}}_{0.3}{\mathrm{MnO}}_3$ has been investigated using spin-resolved photoemission spectroscopy, which has an $\sim 5Å$ probing depth. $M_{\mathrm{SB}}$ shows the full moment at very low temperature but decays much faster than the bulk magnetization $\left(M_B\right)$ upon heating. This result provides direct insight into various novel properties at grain and surface boundaries observed in the polycrystalline samples and junctions of manganese perovskites.