title: Ferroelectricity in ultrathin perovskite films.
abstract: Understanding the suppression of ferroelectricity in perovskite thin films is a fundamental issue that has remained unresolved for decades. We report a synchrotron x-ray study of lead titanate as a function of temperature and film thickness for films as thin as a single unit cell. At room temperature, the ferroelectric phase is stable for thicknesses down to 3 unit cells (1.2 nanometers). Our results imply that no thickness limit is imposed on practical devices by an intrinsic ferroelectric size effect.
authors.affiliation: Materials Science Division, Argonne National Laboratory, Argonne, IL 60439, USA.
authors.forename: Dillon D
authors.initials: DD
authors.lastname: Fong
authors.forename: G Brian
authors.initials: GB
authors.lastname: Stephenson
authors.forename: Stephen K
authors.initials: SK
authors.lastname: Streiffer
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Eastman
authors.forename: Orlando
authors.initials: O
authors.lastname: Auciello
authors.forename: Paul H
authors.initials: PH
authors.lastname: Fuoss
authors.forename: Carol
authors.initials: C
authors.lastname: Thompson