Polaron Ordering in Low-DopingLa1−xSrxMnO3

Abstract

We have found a polaron ordered phase in low-doping rate ${\mathrm{La}}_{1-x}{\mathrm{Sr}}_x{\mathrm{MnO}}_3$ ( $x=0.10\mathrm{}$ and 0.15) by neutron scattering study. The onset temperature of the polaron order coincides with the point of resistivity upturn. The periodicity of the hole lattice is commensurate to the structural lattice translation, the unit cell being given by $2a\times 2b\times 4c$ in cubic perovskite basis. The nominal hole concentration corresponding to this periodicity is $n=0.125\mathrm{}$. The polaron lattice seems to have the tendency to lock into this commensurate structure within a finite concentration range around the nominal value of $x=0.125\mathrm{}$.