Deterministic control of the intrinsic polarization state of ferroelectric thin films is essential for device applications. Independently of the well‐established role of electrostatic boundary conditions and epitaxial strain, the importance of growth temperature as a tool to stabilize a target polarization state during thin film growth is shown here. Full control of the intrinsic polarization orientation of PbTiO3thin films is demonstrated—from monodomain up, through polydomain, to monodomain down as imaged by piezoresponse force microscopy—using changes in the film growth temperature. X‐ray diffraction and scanning transmission electron microscopy reveal a variation of
Temperature‐ and electric‐field‐induced structural transitions in a polydomain ferroelectric can have profound effects on its electrothermal susceptibilities. Here, the role of such ferroelastic domains on the pyroelectric and electrocaloric response is experimentally investigated in thin films of the tetragonal ferroelectric PbZr0.2Ti0.8O3. By utilizing epitaxial strain, a rich set of ferroelastic polydomain states spanning a broad thermodynamic phase space are stabilized. Using temperature‐dependent scanning‐probe microscopy, X‐ray diffraction, and high‐frequency phase‐sensitive pyroelectric measurements, the propensity of domains to reconfigure under a temperature perturbation is quantitatively studied. In turn, the “extrinsic” contributions to pyroelectricity exclusively due to changes between the ferroelastic domain population is elucidated as a function of epitaxial strain. Further, using highly sensitive thin‐film resistive thermometry, direct electrocaloric temperature changes are measured on these polydomain thin films for the first time. The results demonstrate that temperature‐ and electric‐field‐driven domain interconversion under compressive strain diminish both the pyroelectric and the electrocaloric effects, while both these susceptibilities are enhanced due to the exact‐opposite effect from the extrinsic contributions under tensile strain.
more » « less- Award ID(s):
- 1708615
- PAR ID:
- 10462512
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials
- Volume:
- 31
- Issue:
- 5
- ISSN:
- 0935-9648
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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