skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Direct evidence for ferroelectric polar distortion in ultrathin lead titanate perovskite films

Abstract

X-ray photoelectron diffraction is used to directly probe the intracell polar atomic distortion and tetragonality associated with ferroelectricity in ultrathin epitaxial PbTiO{sub 3} films. Our measurements, combined with ab initio calculations, unambiguously demonstrate noncentrosymmetry in films a few unit cells thick, imply that films as thin as three unit cells still preserve a ferroelectric polar distortion, and also show that there is no thick paraelectric dead layer at the surface.

Authors:
; ; ; ; ; ; ; ; ;  [1];  [2];  [3];  [4]
  1. Institut de Physique, Universite de Neuchatel, CH-2000 Neuchatel (Switzerland)
  2. (Switzerland)
  3. (Spain)
  4. (Belgium)
Publication Date:
OSTI Identifier:
20787951
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 73; Journal Issue: 9; Other Information: DOI: 10.1103/PhysRevB.73.094110; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 36 MATERIALS SCIENCE; EPITAXY; FERROELECTRIC MATERIALS; LAYERS; LEAD COMPOUNDS; PEROVSKITE; SURFACES; THIN FILMS; TITANATES; X-RAY DIFFRACTION; X-RAY PHOTOELECTRON SPECTROSCOPY

Citation Formats

Despont, L., Koitzsch, C., Clerc, F., Garnier, M. G., Aebi, P., Lichtensteiger, C., Triscone, J.-M., Garcia de Abajo, F. J., Bousquet, E., Ghosez, Ph., DPMC, Universite de Geneve, 24 Quai Ernest-Ansermet, CH-1211 Geneva 4, Centro Mixto CSIC-UPV/EHU, 20080 San Sebastian, and Departement de Physique, Universite de Liege, B-4000 Sart-Tilman. Direct evidence for ferroelectric polar distortion in ultrathin lead titanate perovskite films. United States: N. p., 2006. Web. doi:10.1103/PHYSREVB.73.0.
Despont, L., Koitzsch, C., Clerc, F., Garnier, M. G., Aebi, P., Lichtensteiger, C., Triscone, J.-M., Garcia de Abajo, F. J., Bousquet, E., Ghosez, Ph., DPMC, Universite de Geneve, 24 Quai Ernest-Ansermet, CH-1211 Geneva 4, Centro Mixto CSIC-UPV/EHU, 20080 San Sebastian, & Departement de Physique, Universite de Liege, B-4000 Sart-Tilman. Direct evidence for ferroelectric polar distortion in ultrathin lead titanate perovskite films. United States. doi:10.1103/PHYSREVB.73.0.
Despont, L., Koitzsch, C., Clerc, F., Garnier, M. G., Aebi, P., Lichtensteiger, C., Triscone, J.-M., Garcia de Abajo, F. J., Bousquet, E., Ghosez, Ph., DPMC, Universite de Geneve, 24 Quai Ernest-Ansermet, CH-1211 Geneva 4, Centro Mixto CSIC-UPV/EHU, 20080 San Sebastian, and Departement de Physique, Universite de Liege, B-4000 Sart-Tilman. Wed . "Direct evidence for ferroelectric polar distortion in ultrathin lead titanate perovskite films". United States. doi:10.1103/PHYSREVB.73.0.
@article{osti_20787951,
title = {Direct evidence for ferroelectric polar distortion in ultrathin lead titanate perovskite films},
author = {Despont, L. and Koitzsch, C. and Clerc, F. and Garnier, M. G. and Aebi, P. and Lichtensteiger, C. and Triscone, J.-M. and Garcia de Abajo, F. J. and Bousquet, E. and Ghosez, Ph. and DPMC, Universite de Geneve, 24 Quai Ernest-Ansermet, CH-1211 Geneva 4 and Centro Mixto CSIC-UPV/EHU, 20080 San Sebastian and Departement de Physique, Universite de Liege, B-4000 Sart-Tilman},
abstractNote = {X-ray photoelectron diffraction is used to directly probe the intracell polar atomic distortion and tetragonality associated with ferroelectricity in ultrathin epitaxial PbTiO{sub 3} films. Our measurements, combined with ab initio calculations, unambiguously demonstrate noncentrosymmetry in films a few unit cells thick, imply that films as thin as three unit cells still preserve a ferroelectric polar distortion, and also show that there is no thick paraelectric dead layer at the surface.},
doi = {10.1103/PHYSREVB.73.0},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 9,
volume = 73,
place = {United States},
year = {Wed Mar 01 00:00:00 EST 2006},
month = {Wed Mar 01 00:00:00 EST 2006}
}
  • Structure{endash}property relationship studies have been performed in the La-modified lead zirconate titanate (PLZT) solution as a function of quenched La impurity content and Zr/Ti ratio. For Zr/Ti ratios of 90/10 and 85/15, an incommensurate antiferroelectric state was found to be stabilized with increasing La content. Temperature-dependent investigations demonstrated that the incommensurate structure becomes pinned into long-time metastable states, rather than transforming to a commensurate phase. Also, the modulation wavelength ({lambda}) was found to increase significantly with the decreasing Zr/Ti ratio and decreasing La content. The results of this study clearly demonstrate that the incommensurately modulated polar structures of PLZT aremore » dependent on the relative antiferroelectric/ferroelectric phase stability, and the concentration of quenched La impurities. {copyright} {ital 1997 American Institute of Physics.}« less
  • Transparent Pb{sub 0.9125}La{sub 0.0975}(Zr{sub 0.65}Ti{sub 0.35}){sub 0.976}O{sub 3} ceramics (conventionally abbreviated as PLZT 9.75/65/35) is a typical relaxor characterized by the absence of the ferroelectric order at the macroscopic scale. In this letter, we report on the observation of complex polar structures on the surface of this material via piezoresponse force microscopy (PFM). The irregular polarization patterns are associated with the formation of a glassy state, where random electric fields destroy the long-range ferroelectric order. The measure of the disorder, the correlation length of {approx}50 nm, was directly deduced from the PFM images. Local poling of relaxor ceramics resulted inmore » the formation of a stable micron-size domain that could be continuously switched under varying dc bias (local relaxor-ferroelectric phase transition). Fractal analysis was applied to analyze the origin of local order in PLZT.« less
  • Electrical studies of materials in the rhombohedral region of the lead zirconate-lead titanate system were conducted. A transition occurring between two ferroelectric states and characterized by electrical and physical anomalies was indicated by a hysteresis anomaly occurring in dissipation and dielectric constant measurements as functions of temperature and effects on the planar coupling coefficient and the resistivity. A phase diagram of the system with 1 wt% NbO/sub 5/ is presented. (L.N.N.)
  • Some time ago we presented evidence that, under nonhydrostatic loading, the F{sub R1} {r_arrow} A{sub O} polymorphic transformation of unpoled PZT 95/5-2Nb (PNZT) ceramic began when the maximum compressive stress equaled the hydro-static pressure at which the transformation otherwise took place. Recently we showed that this simple criterion did not apply to nonhydrostatically compressed, poled ceramic. However, unpoled ceramic is isotropic, whereas poled ceramic has a preferred crystallographic orientation and is mechanically anisotropic. If we further assume that the transformation depends not only on the magnitude of the compressive stress, but also its orientation relative to some feature(s) of PNZT'smore » crystallography, then these disparate results can be qualitatively resolved. It has long been known that this transformation can be triggered in uniaxial compression. Our modified hypothesis makes two predictions for transformation of unpoled polycrystals under uniaxial stress: (i) the transformation should begin when the maximum compressive stress, {sigma}{sub 1}, equals the hydrostatic pressure for transformation, and (ii) a steadily increasing axial stress should be required to drive the transformation.« less
  • Recently we showed that, under nonhydrostatic loading, the F{sub R1}{yields}A{sub O} polymorphic transformation of unpoled lead zirconate titanate 95/5-2Nb (PNZT) ceramic began when the maximum compressive stress equaled the hydrostatic pressure at which the transformation otherwise occurred. More recently we showed that this criterion seemed not to apply to poled ceramic. However, unpoled ceramic is isotropic whereas poled ceramic is not. If we further assume that the transformation depends on both the stress magnitude and its orientation relative to PNZT's structure, these disparate results can be resolved. This modified hypothesis makes two predictions for transformation of unpoled ceramic under uniaxialmore » compression: (i) it will begin when the compressive stress equals the hydrostatic pressure for transformation, and (ii) steadily increasing stress will be required to drive it to completion. Here we present experimental results that confirm these predictions. We then revisit our earlier results for poled and unpoled PNZT. The new hypothesis quantifies the observed effect of shear stress on the mean stress for onset of the transformation of unpoled ceramic and explains previously reported kinetic effects. (c) 2000 Materials Research Society.« less