Theoretical Description of Pseudocubic Manganites

A comprehensive theoretical model for the bulk manganite system La$_{1-x}$(Ca,Sr)$_x$MnO$_3$ is presented. The model includes local and cooperative Jahn-Teller distortions and the on-site Coulomb and exchange interaction. The model is is solved in the single-site dynamical mean field approximation using a solver based on the semiclassical approximation. The model semi-quantitatively reproduces the observed phase diagram for the doping $0 \leq x<0.5$ and implies that the manganites are in the strong coupling region but close to Mott insulator/metal phase boundary. The results establish a formalism for use in a broader range of calculations, for example on heterostructures.