title: A nanoscale shape memory oxide.
abstract: Stimulus-responsive shape-memory materials have attracted tremendous research interests recently, with much effort focused on improving their mechanical actuation. Driven by the needs of nanoelectromechanical devices, materials with large mechanical strain, particularly at nanoscale level, are therefore desired. Here we report on the discovery of a large shape-memory effect in bismuth ferrite at the nanoscale. A maximum strain of up to ~14% and a large volumetric work density of ~600±90 J cm(-3) can be achieved in association with a martensitic-like phase transformation. With a single step, control of the phase transformation by thermal activation or electric field has been reversibly achieved without the assistance of external recovery stress. Although aspects such as hysteresis, microcracking and so on have to be taken into consideration for real devices, the large shape-memory effect in this oxide surpasses most alloys and, therefore, demonstrates itself as an extraordinary material for potential use in state-of-art nanosystems.
authors.affiliation: 1] Department of Physics, Beijing Normal University, Beijing 100875, China [2] Department of Physics, University of California, Berkeley, California 94720, USA [3].
authors.forename: Jinxing
authors.initials: J
authors.lastname: Zhang
authors.forename: Xiaoxing
authors.initials: X
authors.lastname: Ke
authors.forename: Gaoyang
authors.initials: G
authors.lastname: Gou
authors.forename: Jan
authors.initials: J
authors.lastname: Seidel
authors.forename: Bin
authors.initials: B
authors.lastname: Xiang
authors.forename: Pu
authors.initials: P
authors.lastname: Yu
authors.forename: Wen-I
authors.initials: WI
authors.lastname: Liang
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Minor
authors.forename: Ying-Hao
authors.initials: YH
authors.lastname: Chu
authors.forename: Gustaaf
authors.initials: G
authors.lastname: Van Tendeloo
authors.forename: Xiaobing
authors.initials: X
authors.lastname: Ren
authors.forename: Ramamoorthy
authors.initials: R
authors.lastname: Ramesh