title: In situ observation of thermally activated domain memory and polarization memory in an aged K⁺-doped (Ba, Sr)TiO₃ single crystal.
abstract: Different ferroelectric domains are degenerate states of the same ferroelectric phase; thus they are energetically equivalent and, in principle there exists no preference for a particular domain pattern. However, the existence of point defects is considered to stabilize certain preferential domain states. In order to study the temperature violation on such stabilized domains, we performed in situ observation on an aged K⁺-doped (Ba, Sr)TiO₃ single crystal and found that both the domain configuration and polarization state can be memorized after experiencing a thermally activated ferro-para-ferro transition cycle, as manifested by a reappearance of the same domain pattern and double P-E hysteresis loop. In contrast, after the sample was aged in the paraelectric state (>10 min), these memory effects disappeared. The above memory effects are considered to originate from the interaction between point defects and the crystal symmetry driven by a symmetry-conforming tendency of point defects. Such a mechanism suggests that the memory effects are relevant to the existence of acceptor dopant and associated mobile oxygen vacancies, and they are not restricted to a particular dopant. Thus similar memory effects are expected to exist in a wide range of ferroelectric materials with acceptor doping.
authors.affiliation: Multi-disciplinary Materials Research Center, Frontier Institute of Science and Technology, State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an 710049, People's Republic of China. Xuedezhen@gmail.com
authors.forename: Dezhen
authors.initials: D
authors.lastname: Xue
authors.forename: Jinghui
authors.initials: J
authors.lastname: Gao
authors.forename: Huixin
authors.initials: H
authors.lastname: Bao
authors.forename: Yumei
authors.initials: Y
authors.lastname: Zhou
authors.forename: Lixue
authors.initials: L
authors.lastname: Zhang
authors.forename: Xiaobing
authors.initials: X
authors.lastname: Ren