南京航空航天大学学报（英文版）2021，Vol.38Issue(1)：75-83,9.
铁电超晶格中畴变导致的可恢复大电致应变
Large and Recoverable Electrostrain in Strained Ferroelectric Superlattices due to Domain Switching
摘要
Abstract
The ferroelectric superlattices have been widely studied due to their distinguished electromechanical coupling properties. Under different biaxial mismatch strains,ferroelectric superlattices exhibit different domain structures and electromechanical coupling properties. A three-dimensional phase field model is employed to investigate the detailed domain evolution and electromechanical properties of the PbTiO3/SrTiO3(PTO/STO) superlattices with different biaxial mismatch strains. The phase field simulations show that the ferroelectric superlattice exhibits large electrostrain in the stacking direction when an external field is applied. Under a large compressive mismatch strain,vortex domains appear in ferroelectric layers with the thickness of 4 nm. The vortex domains become stable c-domain under a large external electric field,which remains when the electric field is removed. When the initial compressive mismatch strain decreases gradually,the waved or a1/a2 domains replaces the initial vortex domains in the absence of electric field. The fully polarized c-domain by a large electric field switches to diagonal direction domain or a/c domain when the electric field is small. Furthermore,when a biaxial tensile strain is applied to the superlattice, ferroelectric domains switch back to the initial a1/a2 twin-like domain structure,resulting in the recoverable and large electrostrain. This provides an effective way to obtain the large and recoverable electrostrain for the engineering application.关键词
大电致应变/铁电超晶格/畴切换/可恢复畴Key words
large electrostrain/ferroelectric superlattices/domain switching/recoverable domains分类
通用工业技术引用本文复制引用
蒋哲鑫,王杰..铁电超晶格中畴变导致的可恢复大电致应变[J].南京航空航天大学学报（英文版）,2021,38(1):75-83,9.基金项目
This work was supported by the Na?tional Natural Science Foundation of China(Nos.11672264,11972320)and the Zhejiang Provincial Natural Science Foundation(No.LZ17A020001). （Nos.11672264,11972320）
