  Reliable and accurate characterization of the electrocaloric effect is
necessary to understand the intrinsic properties of materials. To date, several
methods have been developed to directly measure the electrocaloric effect.
However, each of them has some limitations, making them less suitable for
characterizing ceramic films, which rely almost exclusively on less accurate
indirect methods. Here, a new approach is proposed to address the process of
rapid heat dissipation in ceramic films and to detect the electrically induced
temperature change before it thermally bonds with the surrounding elements. By
using a polymer substrate that slows heat dissipation to the substrate and fast
infrared imaging, a substantial part of the adiabatic electrocaloric effect in
Pb(Mg1/3Nb2/3)O3-based ceramic films is captured. Infrared imaging provides a
robust technique to reduce the ratio between the adiabatic and the measured
electrocaloric temperature change in micrometer-sized ceramic films to a
single-digit number, ~3.5. The obtained results are validated with another
direct thermometric method and compared with the results obtained with an
indirect approach. Despite different measurement principles, the results
obtained with the two direct methods agree well. The proposed approach is
timely and could open a door to verify the predicted giant electrocaloric
effects in ceramic films, thus accelerating the process of their integration
into functional devices.
