Structural and magnetic properties of the new quantum magnet BaCuTe$_2$O$_6$

TL;DR

This study introduces BaCuTe$_2$O$_6$ as a new quantum magnet with a cubic structure, revealing antiferromagnetic chain order and frustrated interchain interactions, advancing understanding of complex magnetic networks.

Contribution

First synthesis and structural characterization of BaCuTe$_2$O$_6$, revealing its complex magnetic network and magnetic properties through multiple experimental techniques.

Findings

Antiferromagnetic interactions with Curie-Weiss temperature of -33K.

Long-range magnetic order at ~6.3K.

Magnetic excitations resemble spin-1/2 Heisenberg chain continuum.

Abstract

We investigate the structural and magnetic properties of the new quantum magnet BaCuTe$_2$O$_6$. This compound is synthesized for the first time in powder and single crystal form. Synchrotron X-ray and neutron diffraction reveal a cubic crystal structure (P4$_1$32) where the magnetic Cu$^{2+}$ ions form a complex network. Physical properties measurements suggest the presence of antiferromagnetic interactions with a Curie-Weiss temperature of -33K, while long-range magnetic order occurs at the much lower temperature of ~6.3K. The magnetic structure, solved using neutron diffraction, reveals antiferromagnetic order along chains parallel to the a, b and c crystal axes. This is consistent with the magnetic excitations which resemble the multispinon continuum typical of the spin-1/2 Heisenberg antiferromagnetic chain. A consistent intrachain interaction value of ~34K is achieved from the various techniques. Finally the magnetic structure provides evidence that the chains are coupled together in a non-colinear arrangement by a much weaker antiferromagnetic, frustrated hyperkagome interaction.