Electron-lattice coupling, orbital stability and the phase diagram of Ca$_{2-x}$Sr$_x$RuO$_4$

TL;DR

This paper uses Hartree-Fock calculations to explore how electron-lattice interactions influence magnetic states, orbital order, and phase diagrams in Sr/CaRuO4 compounds, revealing that interactions tend to suppress orbital disproportionation.

Contribution

It provides a theoretical model that accounts for the phase diagram and magnetic states of Sr/CaRuO4, incorporating lattice distortions and orbital effects.

Findings

Interactions disfavor orbital disproportionation.

A coherent phase diagram is achieved.

Both commensurate and incommensurate magnetic states are considered.

Abstract

Hartree-Fock calculations are presented of a theoretical model describing the Sr/CaRuO$_4$ family of compounds. Both commensurate and incommensurate magnetic states are considered, along with orbital ordering and the effect of lattice distortions. For reasonable parameter values, interactions disfavor orbital disproportionation. A coherent description of the observed phase diagram is obtained.