Phase diagram of frustrated mixed-spin ladders in the strong-coupling limit

TL;DR

This paper investigates the phase diagram of frustrated mixed-spin ladders in the strong-coupling limit, revealing transitions between ferrimagnetic and spin-liquid states based on exchange interactions.

Contribution

It provides a systematic mapping of mixed-spin ladders onto an effective spin-1/2 model, elucidating their ground-state phases.

Findings

Identification of ferrimagnetic and spin-liquid phases

Mapping of mixed-spin ladders to an effective spin model

Dependence of phases on exchange interaction competition

Abstract

We study the ground-state properties of frustrated Heisenberg ferrimagnetic ladders with antiferromagnetic exchange interactions and two types of alternating sublattice spins. In the limit of strong rung couplings, we show that the mixed spin-1/2 and spin-1 ladders can be systematically mapped onto a spin-1/2 Heisenberg model with additional next-nearest-neighbor exchanges. The system is either in a ferrimagnetic state or in a critical spin-liquid state depending on the competition between the spin exchanges along the legs and the diagonal exchanges.