Chiral entanglement in triangular lattice models

TL;DR

This paper investigates the low energy spectrum and entanglement properties of triangular lattice spin-1/2 models with chiral interactions, revealing geometry-dependent entanglement and evidence of a chiral spin liquid phase.

Contribution

It provides analytical and numerical analysis of chiral entanglement in triangular lattice models, highlighting the role of lattice geometry and identifying a potential chiral spin liquid phase.

Findings

Entanglement depends on lattice geometry due to frustration effects.

Chirality serves as a witness of tripartite entanglement.

Numerical evidence suggests the low energy sector forms a chiral spin liquid.

Abstract

We consider the low energy spectrum of spin-1/2 two-dimensional triangular lattice models subject to a ferromagnetic Heisenberg interaction and a three spin chiral interaction of variable strength. Initially, we consider quasi-one dimensional ladder systems of various geometries. Analytical results are derived that yield the behavior of the ground states, their energies and the transition points. The entanglement properties of the ground state of these models are examined and we find that the entanglement depends on the lattice geometry due to frustration effects. To this end, the chirality of a given quantum state is used as a witness of tripartite entanglement. Finally, the two dimensional model is investigated numerically by means of exact diagonalization and indications are presented that the low energy sector is a chiral spin liquid.