Terahertz and far-infrared response of BaxSr1-xTiO3 films

P. Kuzel (1) , E. Simon (1) , T. Ostapchuk (1) , J. Hlinka (1) , S. Kamba (1) , Edwin Nguema Agnandji (2) , Patrick Mounaix (2) , Jean-Claude Carru (3) , Gabriel Vélu (3)

1 Institute of Physics
2 CPMOH - Centre de physique moléculaire optique et hertzienne
3 LEMCEL - Laboratoire d'Etude des Matériaux et des Composants pour l'Electronique

Here, we report on the experimental study of terahertz (THz) and far-infrared dielectric response of polycrystalline BaxSr1-xTiO3 (x = 0.5, 0.7, and 0.8) films of 0.3-1 mu m thicknesses deposited on a sapphire. THz and far-infrared transmission measurements were performed in 100-420 K temperature range covering the vicinity of TC of their bulk prototypes. We identified all polar optical phonons observed in bulk samples below 400 cm-1 of the same composition including soft and central modes and found some additional features, which we assigned to the depolarizing field effect coming from the structural inhomogeneity and unreleased strain.

Domaines: Optique / photonique

P. Kuzel, E. Simon, T. Ostapchuk, J. Hlinka, S. Kamba, et al.. Terahertz and far-infrared response of BaxSr1-xTiO3 films. Czech-Polish Seminar 2010 on Structural and Ferroelectric Phase Transitions, May 2010, Telč, Czech Republic. pp.966-973, ⟨10.1080/01411594.2010.509608⟩. ⟨hal-00672151⟩