Magnetic, thermal, and magnetocaloric properties of the holmium trialuminide HoAl${}_3$ with polytypic phases

Abstract

We investigate the magnetic, thermal, and magnetocaloric properties of the intermetallic HoAl${}_3$ compounds with two different crystal structures. The room-temperature equilibrium trigonal phase HoAl${}_3$ undergoes an antiferromagnetic (AFM) transition at the Neel temperature $T_{\mathrm{N}}^{\mathrm{tri}}=$ 9.8 K. The AFM ordering of the compound is strong against the magnetic field, so that inverse magnetocaloric effect (MCE) is found even under a magnetic field change of 0-50 kOe. The high-pressure cubic phase HoAl3, prepared by a rapid-solidification process, is antiferromagnetically ordered below $T_{\mathrm{N}}^{\mathrm{cub}}=$ 15 K. Magnetic and specific heat measurements reveal that this long-range AFM state becomes unstable as the temperature drops and then it is replaced by a magnetic glassy state below a spin freezing temperature $T_{\mathrm{f}}=$ 11 K. The successive changes in magnetic state result in complicated temperature and field dependence of the MCE at low temperatures.

Journal of Magnetism and Magnetic Materials Accepted

References in corpus (2)

• Machine Learning Guided Discovery of Gigantic Magnetocaloric Effect in HoB${}_2$ Near Hydrogen Liquefaction Temperature
• Adiabatic temperature change in ErAl2/metal PIT wires: A practical method for estimating the magnetocaloric response of magnetocaloric composites