Nature of the phases in the frustrated XY model on the honeycomb lattice

TL;DR

This study investigates the phase diagram of the frustrated XY model on a honeycomb lattice, revealing a spin-liquid phase at intermediate frustration using advanced variational Monte Carlo methods.

Contribution

It introduces a novel variational approach combining fermionic partons and Jastrow factors to accurately identify quantum phases in the frustrated XY model.

Findings

Identification of a spin-liquid phase at intermediate frustration

Magnetically ordered phases are stabilized at low and high frustration

Enhanced accuracy over classical solutions through correlated wave functions

Abstract

We study the phase diagram of the frustrated XY model on the honeycomb lattice by using accurate correlated wave functions and variational Monte Carlo simulations. Our results suggest that a spin-liquid state is energetically favorable in the region of intermediate frustration, intervening between two magnetically ordered phases. The latter ones are represented by classically ordered states supplemented with a long-range Jastrow factor, which includes relevant correlations and dramatically improves the description provided by the purely classical solution of the model. The construction of the spin-liquid state is based on a decomposition of the underlying bosonic particles in terms of spin-1/2 fermions (partons), with a Gutzwiller projection enforcing no single occupancy, as well as a long-range Jastrow factor.