Giant polarization in super-tetragonal ferroelectric thin films through interphase strain
Abstract
Strain engineering has emerged as a powerful tool to enhance the performance of known functional materials. Here we demonstrate a general and practical method to obtain super-tetragonality and giant polarization using interphase strain. We use this method to create an out-of-plane–to–in-plane lattice parameter ratio of 1.238 in epitaxial composite thin films of tetragonal lead titanate (PbTiO3), compared to 1.065 in bulk. These thin films with super-tetragonal structure possess a giant remanent polarization, 236.3 microcoulombs per square centimeter, which is almost twice the value of known ferroelectrics. The super-tetragonal phase is stable up to 725°C, compared to the bulk transition temperature of 490°C. The interphase-strain approach could enhance the physical properties of other functional materials.
Citation
Zhang , L , Chen , J , Fan , L , Diéguez , O , Cao , J , Pan , Z , Wang , Y , Wang , J , Kim , M , Deng , S , Wang , J , Wang , H , Deng , J , Yu , R , Scott , J F & Xing , X 2018 , ' Giant polarization in super-tetragonal ferroelectric thin films through interphase strain ' , Science , vol. 361 , no. 6401 , pp. 494-497 . https://doi.org/10.1126/science.aan2433
Publication
Science
Status
Peer reviewed
ISSN
0036-8075Type
Journal article
Rights
© 2018, the Author(s). This work has been made available online in accordance with the publisher’s policies. This is the author created accepted version manuscript following peer review and as such may differ slightly from the final published version. The final published version of this work is available at https://doi.org/10.1126/science.aan2433
Collections
Items in the St Andrews Research Repository are protected by copyright, with all rights reserved, unless otherwise indicated.