Charge ordering and long-range interactions in layered transition metal oxides

TL;DR

This paper investigates how long-range Coulomb and short-range dipolar interactions influence charge ordering in layered transition metal oxides, revealing a phase diagram with four distinct phases including Wigner crystal and stripe patterns.

Contribution

It introduces a comprehensive analysis of charge phases considering both Coulomb and dipolar interactions, highlighting their roles in layered transition metal oxides.

Findings

Identification of four charge phases: Wigner crystal, diagonal stripes, loops, and glassy-clumped phase.

Demonstration of how interaction strength and hole density determine phase transitions.

Discussion of temperature, disorder, and lattice effects on phase stability.

Abstract

We study the competition between long-range and short-range interactions among holes within the spin density wave picture of layered transition metal oxides. We focus on the problem of charge ordering and the charge phase diagram. We show that the main interactions are the long-range Coulomb interaction and a dipolar short-range interaction generated by the short-range antiferromagnetic fluctuations. We find four different phases depending on the strength of the dipolar interaction and the density of holes: Wigner crystal, diagonal stripes, horizontal-vertical stripes (loops) and a glassy-clumped phase. We discuss the effect of temperature, disorder and lattice effects on these phases.