Microscopic study on magnetocaloric and electrocaloric effects near the critical point

Adiabatic temperature changes of magnetocaloric/electrocaloric effects are analytically investigated. The analytical studies are based on the microscopic statistical models such as Husimi-Temperley model and Slater model. As a result, we show the characteristic scales of the adiabatic processes correspond to microscopic parameters, namely exchange couplings and Slater energy. The scaled parameter dependence become stronger near the critical point. Furthermore, using a general Hamiltonian method, we clarify the adiabatic temperature changes depend on the relative ratio of characteristic scales. The present study may propose a useful aspect for applications.