Ferroelectric PbTiO3/BaTiO3 superlattices: Growth anomalies and confined modes

Authors
Le Marrec, F Farhi, R El Marssi, M Dellis, JL Karkut, MG Ariosa, D
Citation
F. Le Marrec et al., Ferroelectric PbTiO3/BaTiO3 superlattices: Growth anomalies and confined modes, PHYS REV B, 61(10), 2000, pp. R6447-R6450
Citations number
21
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
PHYSICAL REVIEW B
ISSN journal
10980121 → ACNP
Volume
61
Issue
10
Year of publication
2000
Pages
R6447 - R6450
Database
ISI
SICI code
1098-0121(20000301)61:10<R6447:FPSGAA>2.0.ZU;2-J
Abstract
We have used laser ablation to grow series of PbTiO3/BaTiO3 (PTO/BTO) multi layers with a modulation wavelength Lambda that varies between 50 Angstrom < Lambda < 360 Angstrom. Modeling the x-ray-diffraction patterns of the mul tilayers indicates that the PTO layers are a-axis oriented. The Raman measu rements reinforce this interpretation. The soft-mode Raman line shifts abru ptly in frequency above Lambda = 240 Angstrom due to possible strain relaxa tion of the multilayer, and the Lambda dependent position of an asymmetric line in the vicinity of 200 cm(-1) is modeled as a confined mode, a signatu re of a modulated structure.