# Investigations of the heterometallic Ludwigite Ni${_2}$AlBO${_5}$

## TL;DR

This study explores the magnetic, thermodynamic, dielectric, and structural properties of Ni2AlBO5, revealing a phase transition to antiferromagnetism at 38K and persistent short-range magnetic correlations at higher temperatures.

## Contribution

It provides the first comprehensive investigation of Ni2AlBO5, detailing its structural, magnetic, and dielectric behavior, and identifies its antiferromagnetic transition and magnetic correlations.

## Key findings

- Antiferromagnetic transition at 38K
- Persistence of short-range magnetic correlations at higher temperatures
- Structural similarity to other ludwigite compounds

## Abstract

We present magnetic, thermodynamic, dielectric and structural investigations on the aluminoborate Ni${_2}$AlBO${_5}$, belonging to the ludwigite family. Room temperature structural refinement suggests that the system crystallizes in the orthorhombic $Pbam$ symmetry, in similarity with most members of this material class. Magnetic and thermodynamic measurements shows that the system undergoes a phase transition to an antiferromagnetic state at 38K, signatures of which are also seen in the lattice parameters and the dielectric constant. Short range magnetic correlations appear to persist to much higher temperatures - a regime in which the ac susceptibility exhibits a power law temperature dependence, in agreement with that expected for random exchange Heisenberg antiferromagnetic spin chains.