Ising model with non-reciprocal interactions

TL;DR

This study investigates a 2D Ising model with non-reciprocal interactions, revealing that increased non-reciprocity lowers the critical temperature and induces traveling spin waves opposite to the non-reciprocity direction.

Contribution

The paper introduces a non-reciprocal interaction scheme in the Ising model and analyzes its effects on phase transition and spin wave dynamics through Monte Carlo simulations.

Findings

Critical temperature decreases with non-reciprocity magnitude

Traveling spin waves are observed opposite to the non-reciprocity vector

The temperature decrease depends only on non-reciprocity magnitude

Abstract

Effective interactions that violate Newton's third law of action-reaction symmetry are common in systems where interactions are mediated by a non-equilibrium environment. Extensive Monte Carlo simulations are carried out on a two-dimensional Ising model, where the interactions are modified non-reciprocally. We demonstrate that the critical temperature decreases as the non-reciprocity increases and this decrease depends only on the magnitude of non-reciprocity. Further, travelling spin waves due to the local fluctuations in magnetisation are observed and these spin waves travel opposite to the non-reciprocity vector.