Re-Entrant Quantum Phase Transitions in Antiferromagnetic Spin-1 Ladders

TL;DR

This paper investigates the complex ground-state phase diagram of antiferromagnetic spin-1 ladders, revealing re-entrant phase transitions and correcting previous theoretical predictions using advanced numerical methods.

Contribution

It provides the first detailed numerical analysis of re-entrant quantum phase transitions in spin-1 ladders, challenging earlier sigma-model based predictions.

Findings

Identification of re-entrant phase boundaries

Correction of previous nonlinear-sigma-model predictions

Numerical characterization of phase competition

Abstract

In response to recent chemical attempts to construct higher-spin ladder materials from organic polyradicals, we study the ground-state properties of a wide class of antiferromagnetic spin-1 ladders. Employing various numerical tools, we reveal the rich phase diagram and correct a preceding nonlinear-sigma-model prediction. A variational analysis well interprets the phase competition with particular emphasis on the {\it re-entrant phase boundary} as a function of the rung interaction.