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Title: Colossal Electromechanical Response in Antiferroelectric‐based Nanoscale Multilayers
Abstract The pursuit of smaller, energy‐efficient devices drives the exploration of electromechanically active thin films (<1 µm) to enable micro‐ and nano‐electromechanical systems. While the electromechanical response of such films is limited by substrate‐induced mechanical clamping, large electromechanical responses in antiferroelectric and multilayer thin‐film heterostructures have garnered interest. Here, multilayer thin‐film heterostructures based on antiferroelectric PbHfO3and ferroelectric PbHf1‐xTixO3overcome substrate clamping to produce electromechanical strains >4.5%. By varying the chemistry of the PbHf1‐xTixO3layer (x = 0.3‐0.6) it is possible to alter the threshold field for the antiferroelectric‐to‐ferroelectric phase transition, reducing the field required to induce the onset of large electromechanical response. Furthermore, varying the interface density (from 0.008 to 3.1 nm−1) enhances the electrical‐breakdown field by >450%. Attaining the electromechanical strains does not necessitate creating a new material with unprecedented piezoelectric coefficients, but developing heterostructures capable of withstanding large fields, thus addressing traditional limitations of thin‐film piezoelectrics.  more » « less
Award ID(s):
2102895
PAR ID:
10618413
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Advanced Materials
Volume:
37
Issue:
14
ISSN:
0935-9648
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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