Stripe Charge Ordering in Triangular-Lattice Systems

TL;DR

This paper explores how charge stripe orderings emerge in a triangular-lattice t2g-orbital Hubbard model at electron density 5.5, revealing different orbital and magnetic arrangements influenced by Hund's coupling through numerical analysis.

Contribution

It demonstrates the stabilization of distinct charge stripe patterns driven by Coulomb interactions and Hund's coupling in a triangular-lattice orbital Hubbard model.

Findings

Charge stripes are stabilized by nearest-neighbor Coulomb interaction.

Different stripe patterns depend on the strength of Hund's coupling.

Orbital arrangements influence magnetic and charge orderings.

Abstract

We investigate the ground-state properties of a t2g-orbital Hubbard model on a triangular lattice at electron density 5.5 by using numerical techniques. There appear several types of paramagnetic phases, but we observe in common that one or two orbitals among three orbitals become relevant due to the effect of orbital arrangement. It is found that charge stripes stabilized by the nearest-neighbor Coulomb interaction consist of antiferromagnetic/ferro-orbital chains for small Hund's coupling, while there occurs stripe charge ordering with ferromagnetic/antiferro-orbital chains for large Hund's coupling.