Large reversible magnetocaloric effect in HoMn₂O₅

Magnetocaloric effect (MCE) in polycrystalline HoMn₂O₅ was investigated by isothermal magnetization curves from 2 K to 50 K. A relatively large magnetic entropy change, ΔS_M = 7.8 J/(kg·K), was achieved with the magnetic field up to 70 kOe. The magnetic entropy change is reversible in the whole range of temperature. The contributions of elastic and magnetoelastic energy to the changing of the magnetic entropy are discussed in terms of the Landau theory. The reversibility of MCE with maximal refrigerant capacity R_C = 216.7 J/kg makes polycrystalline HoMn₂O₅ be promising as a magnetic refrigerant.