Elastocaloric response of PbTiO3 Predicted from a first-principles effective Hamiltonian

A first-principles effective Hamiltonian is used in a molecular dynamics simulation to study the elastocaloric effect in PbTiO₃. It is found that the transition temperature is a linear function of uniaxial tensile stress. A negative temperature change is calculated, when the uniaxial tensile stress is switched off, as a function of the initial temperature ΔT(T_initial ). It is predicted that the formation of domain structures under uniaxial tensile stress degrades the effectiveness of the elastocaloric effect.