Ising-XY Transition in Three-dimensional Frustrated Antiferromagnets with Collinear Ordering

TL;DR

This study uses Monte Carlo simulations to analyze the critical behavior of three-dimensional frustrated XY antiferromagnets with collinear ordering, revealing a single first-order transition and critical exponents consistent with XY magnets of similar symmetry.

Contribution

It presents the first detailed Monte Carlo analysis of two frustrated 3D XY antiferromagnets with collinear order, identifying a single first-order transition and matching critical exponents with related XY systems.

Findings

Single first-order transition observed in both models.

Critical exponents align with XY magnets with planar spin ordering.

Models exhibit behavior similar to stacked-triangular antiferromagnets and helimagnets.

Abstract

Using Monte Carlo simulations, we study the critical behavior of two models of frustrated XY antiferromagnets with a collinear spin ordering and with an additional twofold degeneracy of the ground state. We consider a classic antiferromagnet on a body-centered cubic lattice with an additional antiferromagnetic exchange interaction between next-nearest spins, and a ferromagnet with an extra antiferromagnetic intralayer exchange. In both models, a single first-order transition on the discrete and continuous order parameters is found. Observed critical pseudo-exponents are in agreement with exponents of XY magnets with a planar spin ordering like a stacked-triangular antiferromagnet and helimagnets belonging to the same symmetry class.