Spin wave analysis to the spatially-anisotropic Heisenberg antiferromagnet on triangular lattice

TL;DR

This paper investigates the zero-temperature phase diagram of the anisotropic Heisenberg antiferromagnet on a triangular lattice, revealing regions of magnetic order, disorder, and potential spin liquid states through spin wave analysis.

Contribution

It provides a detailed spin wave analysis of the anisotropic triangular lattice model, identifying the stability regions of various magnetic and nonmagnetic phases.

Findings

Quantum fluctuations melt classical structures near J_alpha/J_beta=0.50.

Incommensurate spiral phases persist until J_beta/J_alpha=0.27.

A wide disordered region suggests possible spin liquid behavior.

Abstract

We study the phase diagram at T=0 of the antiferromagnetic Heisenberg model on the triangular lattice with spatially-anisotropic interactions. For values of the anisotropy very close to J_alpha/J_beta=0.50, conventional spin wave theory predicts that quantum fluctuations melt the classical structures, for S=1/2. For the regime J_beta<J_alpha, it is shown that the incommensurate spiral phases survive until J_beta/J_alpha=0.27, leaving a wide region where the ground state is disordered. The existence of such nonmagnetic states suggests the possibility of spin liquid behavior for intermediate values of the anisotropy.