BaCu3O4: High Temperature Magnetic Order in One-Dimensional S=1/2 Diamond-Chains

TL;DR

This study investigates BaCu3O4, revealing it as a unique weakly coupled one-dimensional magnetic system with high-temperature antiferromagnetic order at 336 K, driven by diamond-chain structures of Cu2+ spins.

Contribution

It provides the first detailed analysis of BaCu3O4's magnetic properties, highlighting its high Nel temperature and the role of diamond-chain structures in its magnetic behavior.

Findings

High Nel temperature of 336 K observed.

Magnetic order arises from antiferromagnetic coupling in diamond chains.

Weak inter-chain coupling maintains one-dimensional magnetic characteristics.

Abstract

The magnetic properties of the alkaline earth oxocuprate BaCu3O4 are investigated. We show that the characteristic Cu3O4 layers of this material can be described with diamond chains of antiferromagnetically coupled Cu 1/2 spins with only a weak coupling between two adjacent chains. These Cu3O4 layers seem to represent a so far unique system of weakly coupled one-dimensional magnetic objects where the local AF ordering of the Cu2+ ions leads to an actual net magnetic moment of an isolated diamond chain. We demonstrate a magnetic transition at a high N\'eel temperature T_{N}=336 K.