title: Periodicity Dependence of the Built-in Electric Field in (Ba0.7Ca0.3)TiO3/Ba(Zr0.2Ti0.8)O3 Ferroelectric Superlattices.
abstract: Symmetric ferroelectric superlattices consisting of (Ba0.7Ca0.3)TiO3 (BCT) and Ba(Zr0.2Ti0.8)O3 (BZT) layers were successfully grown on La0.7Sr0.3MnO3 electroded (001)-oriented SrTiO3 substrates by laser molecular beam epitaxy. With the monitor of reflective high-energy electron diffraction, the growth mode and rate were precisely controlled to realize the desired superlattice periodicity as confirmed by both X-ray diffraction and transmission electron microscopy results. The microscopic piezoelectric response and macroscopic ferroelectric properties were investigated as a function of periodicity of the BCTm/BZTm (m = 3, 5, 10, and 15 unit cells) superlattices. The existence of a built-in electric field was confirmed in all the superlattices and its strength was highly dependent on the periodicity. The excellent tunability of built-in electric field opens a path for designing microelectronic devices with various functionalities based on BCTm/BZTm superlattices.
authors.affiliation: School of Materials Science and Engineering, The University of New South Wales , Sydney, New South Wales 2052, Australia.
authors.forename: Qianru
authors.initials: Q
authors.lastname: Lin
authors.affiliation: School of Materials Science and Engineering, The University of New South Wales , Sydney, New South Wales 2052, Australia.
authors.forename: Danyang
authors.initials: D
authors.lastname: Wang
authors.affiliation: Materials Engineering, The University of Queensland , Brisbane, Queensland 4072, Australia.
authors.forename: Zhigang
authors.initials: Z
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Electrical Insulation and Power Equipment, Xi'an Jiaotong University , Xi'an 710049, China.
authors.forename: Wenfeng
authors.initials: W
authors.lastname: Liu
authors.affiliation: Electron Microscopy Unit, University of New South Wales , Sydney, New South Wales 2052, Australia.
authors.forename: Sean
authors.initials: S
authors.lastname: Lim
authors.affiliation: School of Materials Science and Engineering, The University of New South Wales , Sydney, New South Wales 2052, Australia.
authors.forename: Sean
authors.initials: S
authors.lastname: Li
keywords: built-in electric field; ferroelectric superlattice thin films; laser molecular beam epitaxy; lead-free; periodicity dependence