A generalized spin ladder in a magnetic field

TL;DR

This paper explores the phase diagram of a generalized spin ladder model with complex interactions in a magnetic field, combining exact solutions and numerical methods to analyze its low-energy properties and phase behavior.

Contribution

It introduces a comprehensive classification of the low-energy phases of a generalized spin ladder and develops a numerical approach to study non-integrable regimes.

Findings

Complete classification of low-energy phases

Identification of phase transitions in the model

Development of a numerical method for phase analysis

Abstract

We study the phase diagram of coupled spin-1/2 chains with bilinear and (chiral) three-spin exchange interactions in a magnetic field. The model is soluble on a one-parametric line in the space of coupling constants connecting the limiting cases of a single and two decoupled Heisenberg chains with nearest neighbour exchange only. We give a complete classification of the low-energy properties of the integrable system and introduce a numerical method which allows to study the possible phases of spin ladder systems away from the soluble line in a magnetic field.