# Antiferromagnetism in the van der Waals layered spin-lozenge semiconductor CrTe3

## TL;DR

This study investigates the layered compound CrTe3, revealing its semiconducting nature, antiferromagnetic order at 55K, and strong magneto-elastic coupling, making it promising for low-dimensional magnetic applications.

## Contribution

It provides the first detailed characterization of CrTe3's structure, magnetic properties, and potential for monolayer and heterostructure applications.

## Key findings

- CrTe3 is a semiconductor with a 0.3 eV band gap.
- Long-range antiferromagnetic order appears at 55K.
- Strong magneto-elastic coupling is observed.

## Abstract

The crystallographic, magnetic, and transport properties of the van der Waals bonded, layered compound CrTe3 have been investigated on single crystal and polycrystalline materials. The crystal structure contains layers made up of lozenge shaped Cr_4 tetramers. Electrical resistivity measurements show the crystals to be semiconducting, with a temperature dependence consistent with a band gap of 0.3eV. The magnetic susceptibility exhibits a broad maximum near 300K characteristic of low dimensional magnetic systems. Weak anomalies are observed in the susceptibility and heat capacity near 55K, and single crystal neutron diffraction reveals the onset of long range antiferromagnetic order at this temperature. Strongly dispersive spin-waves are observed in the ordered state. Significant magneto-elastic coupling is indicated by the anomalous temperature dependence of the lattice parameters and is apparent in structural optimization in van der Waals density functional theory calculations for different magnetic configurations. The cleavability of the compound is apparent from its handling and is confirmed by first principles calculations, which predict a cleavage energy 0.5J/m^2, similar to graphite. Based on these results, CrTe3 is identified as a promising compound for studies of low dimensional magnetism in bulk crystals as well as magnetic order in monolayer materials and van der Waals heterostructures.