Phase Diagram of the Easy-Axis Triangular-Lattice $J_1\!-\!J_2$ Model

TL;DR

This paper maps the phase diagram of the $S=1/2$ easy-axis triangular-lattice $J_1$-$J_2$ model, revealing a broad spin-liquid region and analyzing the nature of the supersolid phase.

Contribution

It combines density-matrix renormalization group calculations with analytical insights to identify and characterize a spin-liquid region and supersolid phase in the model.

Findings

A significant spin-liquid region exists between the Y and stripe phases.

The supersolid phase lacks a ferromagnetic moment.

The order parameters of the supersolid are characterized.

Abstract

The phase diagram of the $S\!=\!1/2$ easy-axis triangular-lattice $J_1\!-\!J_2$ model is investigated using the density-matrix renormalization group and analytical insights. We find a significant spin-liquid region extending from the Heisenberg limit and residing between the Y phase-known as the magnetic analogue of the "supersolid"-and collinear stripe phase. The order parameters of the supersolid are analyzed and an understanding of its lack of ferromagnetic moment is suggested.