Weakly anisotropic frustrated zigzag spin chain

TL;DR

This paper investigates the phase diagram of a weakly anisotropic frustrated spin-1/2 zigzag chain using variational mean-field, perturbation theory, and finite-size calculations, revealing three distinct phases and their boundary behaviors.

Contribution

It provides a detailed analysis of the phase boundaries and transition characters in a weakly anisotropic frustrated spin chain, which was not thoroughly explored before.

Findings

Identification of three phases: ferromagnetic, spin-liquid, and incommensurate.

Characterization of phase boundary behaviors and transition types.

Analysis of weak anisotropy effects on the phase diagram.

Abstract

The frustrated spin-1/2 model with weakly anisotropic ferromagnetic nearest-neighbor and antiferromagnetic next-nearest-neighbor exchanges is studied with use of variational mean-field approach, scaling estimates of the infrared divergencies in the perturbation theory and finite-size calculations. The ground state phase diagram of this model contains three phases: the ferromagnetic phase, the commensurate spin-liquid phase and the incommensurate phase. The non-trivial behavior of the boundaries between these phases and the character of the phase transitions in case of weak anisotropy are determined.