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Title: Probing Antiferroelectric‐Ferroelectric Phase Transitions in PbZrO 3 Capacitors by Piezoresponse Force Microscopy

Functional characterization of antiferroelectric (AFE) materials typically involves macroscopic testing of their nonlocal integrated information on their dielectric properties, such as polarization hysteresis loops, field‐dependent strain, and capacitance while the local AFE properties have been rarely addressed. Here, a new protocol is demonstrated for local probing of the antiferroelectric/ferroelectric (AFE/FE) phase transition in PbZrO3capacitors by piezoresponse force microscopy (PFM). PFM spectroscopy of the local AFE/FE phase transition parameters is performed and their spatial variability via two‐dimensional mapping is investigated. It is shown that AFE hysteresis loops recorded by PFM in the bias‐on regime exhibit four characteristic amplitude peaks. Within the framework of Landau theory, these features are attributed to a considerable increase in the electromechanical strain response due to the dielectric constant divergence during AFE/FE phase transitions. The proposed approach can be used to differentiate between the antiferroelectric and nonpolar dielectric phases in functional devices using the electrically induced polarization.

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Author(s) / Creator(s):
 ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Functional Materials
Medium: X
Sponsoring Org:
National Science Foundation
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