Slow Magnetic Order-Order Transition in the Spin Chain Antiferromagnet Ca3Co2O6

TL;DR

This study uncovers a rare, slow magnetic order-order transition in Ca3Co2O6, revealing complex magnetic behavior in a spin chain antiferromagnet through neutron diffraction analysis.

Contribution

It reports the discovery of an unusual, slow magnetic transition between two ordered states in Ca3Co2O6, a novel phenomenon in spin chain antiferromagnets.

Findings

Unusual slow transition takes several hours

Transition is incomplete and occurs between two magnetic orders

Different magnetic phases characterized by distinct propagation vectors

Abstract

Using powder neutron diffraction we have discovered an unusual magnetic order-order transition in the Ising spin chain compound Ca3Co2O6. On lowering the temperature an antiferromagnetic phase with propagation vector k=(0.5,-0.5,1) emerges from a higher temperature spin density wave structure with k=(0, 0, 1.01). This transition occurs over an unprecedented time-scale of several hours and is never complete.