A reentrant superspin glass state and magnetization steps in the oxyborate Co2AlBO5

TL;DR

This study investigates Co2AlBO5, revealing a reentrant superspin glass state below 10.6 K, long-range magnetic order at 42 K, and field-induced magnetization steps, distinguishing it from similar ludwigite compounds.

Contribution

It reports the discovery of a reentrant superspin glass phase and magnetization steps in Co2AlBO5, a ludwigite oxyborate, with detailed magnetic and structural characterization.

Findings

Long-range magnetic order at 42 K.

Reentrant superspin glass phase below 10.6 K.

Magnetization steps under applied magnetic fields.

Abstract

An oxyborate Co2AlBO5 belonging to the ludwigite family is investigated using structural, thermodynamic, dielectric and magnetic measurements. Magnetic measurements indicate that this system is seen to exhibit long range magnetic ordering at T{_N} = 42 K, signatures of which are also seen in the specific heat, dielectric susceptibility, and the lattice parameters. The absence of a structural phase transition down to the lowest measured temperatures, distinguishes it from the more extensively investigated Fe-based ludwigites. At low temperatures, the system is seen to stabilize in a reentrant superspin glass phase at T{_G} = 10.6 K from within the magnetically ordered state. This ground state is also characterized by magnetic field induced metamagnetic transitions, which at the lowest measured temperatures exhibit a number of sharp magnetization steps, reminiscent of that observed in the mixed valent manganites.