Aging-induced domain memory in acceptor-doped perovskite ferroelectrics associated with ferroelectric-ferroelectric transition cycle

¹ Multi-disciplinary Materials Research Center, Frontier Institute of Science and Technology, State Key Lab of Electrical Insulation and Power Equipment, Xi'an Jiaotong University Xi'an, 710049, China
² State Key Lab for Mechanical Behaviors of Materials and MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter, Xi'an Jiaotong University - Xi'an, 710049, China
³ Ferroic Physics Group, National Institute for Materials Science - Tsukuba, 305-0047, Ibaraki, Japan

^a GAO.Jinghui@nims.go.jp

Received: 29 August 2011
Accepted: 9 September 2011

Abstract

Perovskite ferroelectrics naturally exhibit multiple energetically equivalent domain states; thus, a certain domain state or a certain domain pattern is not expected to reappear once it is disturbed by a phase transition; i.e., there should exist no “domain memory”. This letter, however, provides direct evidence with in situ optical microscopy for a domain memory effect in an aged K⁺-doped BaTiO₃ single crystal during a ferroelectric-ferroelectric transition cycle between tetragonal and orthorhombic phase. By contrast, the domain memory effect is absent in an unaged sample. These results suggest that the domain memory effect is associated with point defect migration during aging. Our findings can be explained by a symmetry-conforming tendency of point defects.