Please use this identifier to cite or link to this item: http://hdl.handle.net/10397/4995
PIRA download icon_1.1View/Download Full Text
Title: Vanishing critical thickness in asymmetric ferroelectric tunnel junctions : first principle simulations
Authors: Cai, MQ
Zheng, Y
Ma, PW
Woo, CH 
Issue Date: 15-Jan-2011
Source: Journal of applied physics, 15 Jan. 2011, v. 109, no. 2, 024103, p. 1-6
Abstract: The stability of the remnant polarization in the ferroelectric barrier layer is a prerequisite to applications involving ferroelectric tunnel junctions (FTJs) or capacitors. One of the most important issues in the pursuit of further developments in this area is to overcome the limitations due to the critical thickness, below which the ferroelectric polarization disappears. In this paper we report first-principle density-functional calculations of the charge distribution and polarization in an asymmetric FTJ (A-FTJ), i.e., one with dissimilar electrodes. We found that a significant and stable polarization can be retained down to thicknesses as small as 0.8 nm two unit-cells in a BaTiO₃thin film between Pt and SrRuO₃electrodes, quite unlike the case of symmetric FTJs. We trace this surprising result to the large electric field produced by the charge transfer between the electrodes caused by their different electronic environments, which acts against the depolarization field and enhances the ferroelectricity, leading to the reduction, or even the complete elimination of the depolarization field, leading to the vanishing of the critical thickness. We speculate that this is a general result for A-FTJs, which could be of importance to applications of ferroelectric thin films and tunneling junctions or capacitors where the presence of the critical thickness is a limiting factor.
Keywords: Ab initio calculations
Barium compounds
Charge exchange
Density functional theory
Dielectric polarisation
Ferroelectric capacitors
Ferroelectric thin films
Platinum
Strontium compounds
Tunnelling
Publisher: American Institute of Physics
Journal: Journal of applied physics 
ISSN: 0021-8979
EISSN: 1089-7550
DOI: 10.1063/1.3532000
Rights: © 2011 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in M. Q. Cai et al., J. Appl. Phys. 109, 024103 (2011) and may be found at http://link.aip.org/link/?jap/109/024103.
Appears in Collections:Journal/Magazine Article

Files in This Item:
File Description SizeFormat 
Cai_Vanishing_critical _thickness.pdf1.48 MBAdobe PDFView/Open
Open Access Information
Status open access
File Version Version of Record
Access
View full-text via PolyU eLinks SFX Query
Show full item record

Page views

86
Last Week
7
Last month
Citations as of May 22, 2022

Downloads

197
Citations as of May 22, 2022

SCOPUSTM   
Citations

29
Last Week
0
Last month
0
Citations as of May 20, 2022

WEB OF SCIENCETM
Citations

29
Last Week
0
Last month
0
Citations as of May 19, 2022

Google ScholarTM

Check

Altmetric


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.