Experimental benchmark of the quantum-classical crossover in a spin ladder

TL;DR

This study experimentally investigates the quantum-classical crossover in a spin ladder system, revealing that lattice topology can suppress quantum effects despite the intrinsic quantum nature of the model.

Contribution

It provides an experimental benchmark demonstrating how lattice topology influences the suppression of quantum fluctuations in a spin ladder system.

Findings

Classical mean-field theory accurately describes magnetization curves.

Quantum Monte Carlo confirms strong quantum fluctuations are suppressed.

Lattice topology plays a crucial role in quantum-classical crossover.

Abstract

We report a spin-(1/2, 5/2) three-leg ladder realized in a radical-Mn polymer, exhibiting an antiferromagnetic transition and magnetization curves accurately described by classical mean-field theory. Although the underlying spin model intrinsically supports strong quantum fluctuations, as confirmed by quantum Monte Carlo simulations, the real system shows an anomalously complete suppression of quantum behavior. These findings provide a key experimental benchmark for the quantum-classical crossover and suggest that lattice topology can play a crucial role in tuning the balance between quantum and classical physics in strongly correlated systems.