Tunable magnetocaloric effect and enhanced refrigerant capacity in composite-like oxide heterostructures

Abstract

We report a detailed study of the magnetocaloric effect in heterostructures of La2NiMnO6 and La2/3Sr1/3MnO3. The shape, width and magnitude of the temperature dependence of the magnetic entropy change (∆Sm) for these multilayer samples can be tuned and controlled by changing their layout. A large ∆Sm over a wide temperature range which goes beyond room temperature is observed in all samples. We observe a temperature-independent table-top-like ∆Sm over a temperature range as large as 100 K in the trilayer samples. La2NiMnO6 double perovskite with multiple magnetic phase transitions is the key to tuning and shaping the temperature dependence of the magnetic entropy changes to suit the requirements of several cooling cycles.