Anomalous magnetization process in frustrated spin ladders

TL;DR

This paper investigates unusual magnetization behaviors in frustrated S=1 two-leg spin ladders at zero temperature, identifying specific magnetization plateaux and anomalies through combined analytical and numerical methods.

Contribution

It provides a comprehensive analysis of magnetization plateaux in frustrated spin ladders using both analytical and numerical techniques, highlighting the existence of the M=Ms/2 plateau.

Findings

Confirmation of the M=Ms/2 plateau in frustrated ladders

Identification of additional plateaux at M=Ms/4 and 3Ms/4

Consistent results from analytical and numerical methods

Abstract

We study, at T=0, the anomalies in the magnetization curve of the S=1 two-leg ladder with frustrated interactions. We focus mainly on the existence of the $M=\Ms/2$ plateau, where $\Ms$ is the saturation magnetization. We use analytical methods (degenerate perturbation theory and non-Abelian bosonization) as well as numerical methods (level spectroscopy and density matrix renormalization group), which lead to the consistent conclusion with each other. We also touch on the $M=\Ms/4$ and $M=(3/4)\Ms$ plateaux and cusps.