# Anisotropy in the magnetization and magnetoelectric response of single crystalline Mn$_{4}$Ta$_{2}$O$_{9}$

## TL;DR

This study investigates the anisotropic magnetic and magnetoelectric properties of single-crystalline Mn4Ta2O9, revealing unique magnetic structures and directional-dependent magnetoelectric coupling through temperature, neutron diffraction, and electric field measurements.

## Contribution

It provides new insights into the anisotropic magnetization and magnetoelectric response of Mn4Ta2O9, highlighting differences from related compounds and elucidating the magnetic structure via neutron diffraction.

## Key findings

- Magnetization is anisotropic with a weak ferromagnetic component.
- Magnetic structure consists of antiferromagnetically coupled ferromagnetic chains.
- Magnetoelectric response varies with direction, showing different signs along different axes.

## Abstract

We report temperature dependent magnetization and neutron diffraction measurements on the corundum related magnetoelectric antiferromagnet Mn$_{4}$Ta$_{2}$O$_{9}$. Measurements performed on a single crystalline specimen reveal that the magnetization is anisotropic, and a weak ferromagnetic component emerges well within the antiferromagnetically ordered state. Powder neutron diffraction measurements indicate that the magnetic structure comprises of antiferromagnetically coupled ferromagnetic chains of Mn$^{2+}$ spins aligned along the trigonal $c$ axis, in contrast to that reported in other isostructural members of this family. Magnetic measurements performed under a periodic electric field indicate that the magnetoelectric response is also anisotropic, with this coupling along the trigonal $c$ axis and that perpendicular to it having different signs.