Electric-Field-Controlled Thermal Switch in Ferroelectric Materials Using First-Principles Calculations and Domain-Wall Engineering

Ferroelectric materials attract attention as potential solid-state thermal switches, due to various phenomena near their solid-state phase transition. In principle these phenomena could also be triggered by an external electric field, though recent experiments on thin films have shown only weak effects. The authors explore this issue by solving the linearized Boltzmann equation with first-principles force constants, to study the thermal conductivity of PbTiO₃ as a function of electric field. The results emphasize the need for large-domain samples and lower temperatures, to have the best chance at large voltage-controlled thermal switching in this class of materials.