Low Working Temperature of Erbium Orthophosphate ErPO4 with Large Magnetocaloric Effect

Abstract

Erbium orthophosphate ErPO₄ was successfully prepared. The XRD pattern analyses have proved that the ErPO₄ crystallizes in the tetragonal structure (I4₁/amd). Under a magnetic field of 50 kOe, the magnetic entropy change (− ΔS_M) reaches 23.78 J/kg K at 2.6 K for ErPO₄. The value of the relative cooling power is 475 J/kg. The lowest temperature and the large MCE have inferred that ErPO₄ is a potential candidate for sub-kelvin magnetic refrigeration applications.