Electrocaloric and barocaloric effects in multicaloric BaTiO₃

Ferroelectric materials typically show large changes of polarization and volume near first‑order phase transitions at the Curie temperature. These large changes can be exploited by driving the transitions using electric field or hydrostatic pressure, resulting in large electrocaloric or barocaloric effects. I will show that single‑crystal and polycrystalline samples of BaTiO₃ display significant electrocaloric [1] and barocaloric [2] effects at the very sharp first-order ferroelectric phase transition near 400 K. Both caloric effects may be driven in full by relatively small external fields, thus yielding giant‑strength electrocaloric and barocaloric effects.