Evolution of ferroelectricity in ultrathin PbTiO 3 films as revealed by electric double layer gating.

Autor: Nishino R; Department of Applied Physics and Quantum-Phase Electronics Center, University of Tokyo, Bunkyo, Tokyo, 113-8656, Japan. Nishino@kwsk.t.u-tokyo.ac.jp., Fujita TC; Department of Applied Physics and Quantum-Phase Electronics Center, University of Tokyo, Bunkyo, Tokyo, 113-8656, Japan., Kagawa F; Department of Applied Physics and Quantum-Phase Electronics Center, University of Tokyo, Bunkyo, Tokyo, 113-8656, Japan.; RIKEN Center for Emergent Matter Science (CMES), Wako, Saitama, 351-0198, Japan., Kawasaki M; Department of Applied Physics and Quantum-Phase Electronics Center, University of Tokyo, Bunkyo, Tokyo, 113-8656, Japan.; RIKEN Center for Emergent Matter Science (CMES), Wako, Saitama, 351-0198, Japan.
Jazyk: angličtina
Zdroj: Scientific reports [Sci Rep] 2020 Jul 02; Vol. 10 (1), pp. 10864. Date of Electronic Publication: 2020 Jul 02.
DOI: 10.1038/s41598-020-67580-8
Abstrakt: Ferroelectricity in ultrathin films is destabilized by depolarization field, which leads to the reduction of spontaneous polarization or domain formation. Here, thickness dependence of remnant polarization in PbTiO 3 films is electrically revealed down to 2.6 nm by controlling the polarization direction with employing an electric double layer gating technique to suppress leakage current in ultrathin films. The remnant polarization for a 17 nm-thick film is similar to bulk value ~ 60 μC cm -2 and reduces to ~ 20 μC cm -2 for a 2.6 nm-thick film, whereas robust ferroelectricity is clearly observed in such ultrathin films. In-situ X-ray diffraction measurements under an external electric field reveal that the reduced tetragonality in ultrathin films is mostly recovered by cancelling out the depolarization field. Electric double layer gating technique is an excellent way for exploring physical properties in ultrathin ferroelectric films.
Databáze: MEDLINE
Externí odkaz:
Nepřihlášeným uživatelům se plný text nezobrazuje