Identification of an RVB liquid phase in a quantum dimer model with competing kinetic terms

TL;DR

This paper demonstrates that a quantum dimer model with competing kinetic terms on a triangular lattice can host a resonating valence bond (RVB) phase, highlighting its generic emergence in such models through numerical simulations.

Contribution

It introduces a new effective quantum dimer model derived from a spin-orbital model of LiNiO₂, showing the RVB phase arises from competing kinetic terms.

Findings

RVB phase exists for a finite parameter range

RVB phase connects to the Rokhsar-Kivelson model RVB phase

Competing interactions generally induce RVB phases in QDMs

Abstract

Starting from the mean-field solution of a spin-orbital model of LiNiO$_2$, we derive an effective quantum dimer model (QDM) that lives on the triangular lattice and contains kinetic terms acting on 4-site plaquettes and 6-site loops. Using numerical exact diagonalizations and Green's function Monte Carlo simulations, we show that the competition between these kinetic terms leads to a resonating valence bond (RVB) state for a finite range of parameters. We also show that this RVB phase is connected to the RVB phase identified in the Rokhsar-Kivelson model on the same lattice in the context of a generalized model that contains both the 6--site loops and a nearest-neighbor dimer repulsion. These results suggest that the occurrence of an RVB phase is a generic feature of QDM with competing interactions.