Magnetocaloric effect and critical behavior in arylamine-based copper chloride layered organic-inorganic perovskite

Layered organic-inorganic hybrid perovskites have been the focus of much research regarding their optoelectronic and multiferroic properties. Here, we demonstrate the presence of a large magnetocaloric effect in the ferromagnetic layered perovskite phenylmethylammonium copper chloride ((PMA)2CuCl4) below the Curie temperature of ∼9.5 K. We measure a magnetic entropy change ranging from 0.88 J/kg.K to 2.98 J/kg.K in applied fields of 10 kOe and 70 kOe, respectively. We also study the nature of the magnetic phase transition using critical isotherm analysis. The critical exponents are consistent with the 2D-XY spin model