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Title: Mechanically controllable nonlinear dielectrics
Strain-sensitive Ba x Sr 1− x TiO 3 perovskite systems are widely used because of their superior nonlinear dielectric behaviors. In this research, new heterostructures including paraelectric Ba 0.5 Sr 0.5 TiO 3 (BSTO) and ferroelectric BaTiO 3 (BTO) materials were epitaxially fabricated on flexible muscovite substrate. Through simple bending, the application of mechanical force can regulate the dielectric constant of BSTO from −77 to 36% and the channel current of BTO-based ferroelectric field effect transistor by two orders. The detailed mechanism was studied through the exploration of phase transition and determination of band structure. In addition, the phase-field simulations were implemented to provide theoretical support. This research opens a new avenue for mechanically controllable components based on high-quality oxide heteroepitaxy.
Authors:
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Award ID(s):
1744213
Publication Date:
NSF-PAR ID:
10155938
Journal Name:
Science Advances
Volume:
6
Issue:
10
Page Range or eLocation-ID:
eaaz3180
ISSN:
2375-2548
Sponsoring Org:
National Science Foundation
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