Tailoring the Magnetocaloric Effect in La2NiMnO6 Thin Films

Efficient, environmentally friendly magnetic refrigeration at room temperature requires a material with a large magnetocaloric effect (MCE) in the desired temperature range. Prototypes already outperform conventional refrigerators, but expanding the operating range remains a challenge, as often the MCE is narrowly limited to the vicinity of the magnetic transition temperature. This study shows that, for a magnetic insulator with two competing phases leading to different transition temperatures, varying thin-film growth parameters can significantly improve the range by tuning the proportion of both phases, leading to nearly temperature-independent MCE over a range of more than 100 K.