On the persistence of polar domains in ultrathin ferroelectric capacitors

0484515 - FZÚ 2018 RIV GB eng J - Journal Article
Zubko, P. - Lu, H. - Bark, C.-W. - Martí, Xavier - Santiso, J. - Eom, C.-B. - Catalan, G. - Gruverman, A.
On the persistence of polar domains in ultrathin ferroelectric capacitors.
Journal of Physics-Condensed Matter. Roč. 29, č. 28 (2017), s. 1-8, č. článku 284001. ISSN 0953-8984. E-ISSN 1361-648X
R&D Projects: GA ČR GB14-37427G
Institutional support: RVO:68378271
Keywords : ultrathin barium titanate * tunnel junctions * ferroelectric domains * polarization screening * retention * negative capacitance
OECD category: Condensed matter physics (including formerly solid state physics, supercond.)
Impact factor: 2.617, year: 2017

The instability of ferroelectric ordering in ultra-thin films is one of the most important
fundamental issues pertaining realization of a number of electronic devices with enhanced functionality, such as ferroelectric and multiferroic tunnel junctions or ferroelectric field effect transistors. In this paper, we investigate the polarization state of archetypal ultrathin (several nanometres) ferroelectric heterostructures: epitaxial single-crystalline BaTiO3 films sandwiched between the most habitual perovskite electrodes, SrRuO3, on top of the most used perovskite substrate, SrTiO3. We use a combination of piezoresponse force microscopy, dielectric measurements and structural characterization to provide conclusive evidence for the ferroelectric nature of the relaxed polarization state in ultrathin BaTiO3 capacitors.

Permanent Link: http://hdl.handle.net/11104/0279685