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Updated: Aug 19, 2026
Chemical Synthesis of Porous Barium Titanate Thin Film and Thermal Stabilization of Ferroelectric Phase by Porosity-Induced Strain
Published on: March 27, 2018
Ferroelectricity and tetragonality in ultrathin PbTiO3 films
Céline Lichtensteiger1, Jean-Marc Triscone, Javier Junquera
1DPMC, Université de Genéve, 24 Quai Ernest-Ansermet, CH-1211 Genéve 4, Switzerland. Celine.Lichtensteiger@physics.unige.ch
Abstract:
The evolution of tetragonality with thickness has been probed in epitaxial c-axis oriented PbTiO3 films with thicknesses ranging from 500 down to 24 A. High resolution x ray pointed out a systematic decrease of the c-axis lattice parameter with decreasing film thickness below 200 A. Using a first-principles model Hamiltonian approach, the decrease in tetragonality is related to a reduction of the polarization attributed to the presence of a residual unscreened depolarizing field. It is shown that films below 50 A display a significantly reduced polarization but still remain ferroelectric.
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