Giant mechanically-mediated electrocaloric effect in ultrathin ferroelectric capacitors at room temperature

Using a phenomenological approach, we demonstrate that a giant mechanically-mediated electrocaloric effect can be obtained in ultrathin ferroelectric SrRuO₃/BaTiO₃/SrRuO₃ capacitors at room temperature. Our results show that the electrocaloric properties of such capacitors can be systematically tuned by applying an external stress. The depolarizing field, whose effect is usually ignored in the literature, is found to be detrimental to the electrocaloric response, especially for the thinner films. Moreover, a remarkable enhancement and broadening of the electrocaloric response can be achieved in relatively thick films under compressively loaded conditions compared with the unloaded case.