Ho6FeSb2: Potential magnetic refrigerant with improved magnetocaloric effect

The magnetic and magnetocaloric characteristics of Ho6FeSb2 have been investigated. The compound crystallizes in Fe2P type hexagonal crystal structure (P62m) with lattice parameters a, b = 8.1046 angstrom and c = 4.1470 angstrom. There are 2 second-order ferromagnetic transitions occurring at temperatures T1 = 56 K and T2 = 34 K. The occurrence of subsequent second-order transitions opens the door to hysteresis-free magnetocaloric effect across wide temperature span. The study utilizes different magnetocaloric figures of merit, including isothermal magnetic entropy change, relative cooling power, and temperature-averaged entropy change. The alloy has a maximum relative cooling power of 710 J/kg in 0-5 T, with the temperature-averaged entropy change value being close to the isothermal magnetic entropy change value, making it suitable for hysteresis-free magnetocaloric applications. We have studied the electrical transport properties of the alloy and estimated a maximum magnetoresistance of-9% around T1.

Automated summary

The magnetic and magnetocaloric characteristics of Ho6FeSb2 have been studied. The compound exhibits two second-order ferromagnetic transitions, enabling hysteresis-free magnetocaloric effect across a wide temperature range. The alloy has high relative cooling power and magnetoresistance, making it suitable for hysteresis-free magnetocaloric applications.