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Title: Heterogeneous field response of hierarchical polar laminates in relaxor ferroelectrics
Understanding the microscopic origin of the superior electromechanical response in relaxor ferroelectrics requires knowledge not only of the atomic-scale formation of polar nanodomains (PNDs) but also the rules governing the arrangements and stimulated response of PNDs over longer distances. Using x-ray coherent nanodiffraction, we show the staggered self-assembly of PNDs into unidirectional mesostructures that we refer to as polar laminates in the relaxor ferroelectric 0.68PbMg1/3Nb2/3O3-0.32PbTiO3(PMN-0.32PT). We reveal the highly heterogeneous electric-field–driven responses of intra- and interlaminate PNDs and establish their correlation with the local strain and the nature of the PND walls. Our observations highlight the critical role of hierarchical lattice organizations on macroscopic material properties and provide guiding principles for the understanding and design of relaxors and a wide range of quantum and functional materials.  more » « less
Award ID(s):
2329111
PAR ID:
10534629
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
AAAS
Date Published:
Journal Name:
Science
Volume:
384
Issue:
6703
ISSN:
0036-8075
Page Range / eLocation ID:
1447-1452
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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