Charge and orbital ordering in underdoped La1-xSrxMnO3

TL;DR

This paper investigates the complex interplay of spin, charge, and orbital orderings in underdoped La1-xSrxMnO3 using Hartree-Fock calculations, revealing nearly degenerate states and a charge-modulated ferromagnetic state near x=1/8.

Contribution

It introduces a model-based analysis of charge and orbital ordering in La1-xSrxMnO3, highlighting the stability of modulated states and their relation to experimental observations.

Findings

Charge and orbital modulated states are nearly degenerate with ferromagnetic states at x=1/8.

A ferromagnetic state with charge modulation along the c-axis is consistent with experimental data.

Multiple stable ordered states suggest complex phase competition in the material.

Abstract

We have explored spin, charge and orbitally ordered states in La1-xSrxMnO3 (0 < x < 1/2) using model Hartree-Fock calculations on d-p-type lattice models. At x=1/8, several charge and orbitally modulated states are found to be stable and almost degenerate in energy with a homogeneous ferromagnetic state. The present calculation indicates that a ferromagnetic state with a charge modulation along the c-axis which is consistent with the experiment by Yamada et al. might be responsible for the anomalous behavior around x = 1/8.