Acoustic properties of nanoscale oxide heterostrutures probed by UV Raman spetrosopy

A. BRUCHAUSEN, N.D.LANZILLOTTI-KIMURA,A. FAINSTEIN,A SOUKIASSIAN,D. A. TENNE,D. SHLOM, X. X. XI, AND A. CANTARERO

Paris, Francia

Conferencia; 12th International Conference on Phonon Scattering in Condensed Matter “Phonons 2007”; 2007

We study high quality molecular-beam epitaxy grown BaTiO3/SrTiO3 superlattices using ultraviolet Raman spectroscopy. In the low energy spectral region, acoustic phonon doublets are observed. These are due to the artifcial superlattice periodicity and consequent folding of the acoustic phonon dispersion. From the study of samples with di erent BaTiO3/SrTiO3 layer thicknesses the efective sound velocities within each of the layers are obtained. using ultraviolet Raman spectroscopy. In the low energy spectral region, acoustic phonon doublets are observed. These are due to the artifcial superlattice periodicity and consequent folding of the acoustic phonon dispersion. From the study of samples with di erent BaTiO3/SrTiO3 layer thicknesses the efective sound velocities within each of the layers are obtained.