Atomic Simulation for Lattice Structure of La/SrMnO₃ Superlattice

Abstract

We studied in detail the lattice transition and local lattice structure (including Jahn-Teller distortion) in LaMnO3/SrMnO3surperlattices by classical atomistic simulation. For a certain doping density, it is found that the superlattices with short modulation period have small lattice energies and larger differences among lattice parametersa,b/√2 andc. The average La-Mn (Mn3+-O) distance is larger than the average Sr-Mn (Mn4+-O) distance for all doping densities and superlattice configurations at certain doping density. The standard deviation of Mn-O bond lengths and Jahn-Teller distortion of MnO6octahedra have been calculated. Both the standard deviation and Jahn-Teller distortion of Mn3+O6octahedra in the superlattices are much smaller than those of Mn3+O6octahedra in LaMnO3, while Mn4+O6octahedra in the superlattices have the smallest lattice distortion, but larger than those in SrMnO3.