Publications
2008

N. D. Scarisoreanu , G. Dinescu, R. Birjega, M. Dinescu, D. Pantelica, G. Velisa, N. Scintee, and A. C. Galca “SBN thin films growth by RF plasma beam assisted pulsed laser deposition”, Appl. Phys. A, 93, 795–800 (2008) (published online: 2 July 2008).
SBN thin films were grown on MgO and Silicon substrates by PLD and RF-PLD (radiofrequency assisted PLD) starting from single crystal Sr0.6Ba0.4Nb2O6 and ceramic Sr0.5Ba0.5Nb2O6 stoichiometric targets. Morphological and structural analyses were performed on the SBN layers by AFM and XRD and optical properties were measured by spectroellipsometry. The films composition was determined by Rutherford Backscattering Spectrometry. The best set of experimental conditions for obtaining crystalline, c-axis preferential texture and with dominant 31° in-plane orientation relative to the MgO (100) axis is identified. [DOI: 10.1007/s00339-008-4753-2]

V. Ion, A. C. Galca, N. D. Scarisoreanu1, M. Filipescu1, and M. Dinescu “Spectroscopic ellipsometry study of amorphous SrxBa1−xNb2O6 thin films obtained by pulsed laser deposition”, physica status solidi c, 5, pp. 1180-1183 (2008) (published online 18 March 2008).
Optical properties of amorphous Strontium Barium Niobate (a-SBN) thin films are investigated using spectroscopic ellipsometry. Since the SBN can be applied to optoelectronic devices, the dispersion of refractive index is desirable. The films are obtained by Pulsed Laser Deposition (PLD) onto MgO and Si substrates by targeting a SBN:60 monocrystal. The dielectric function of a-SBN is approximated using a single Tauc-Lorentz oscillator model. Thicknesses of the films and of their rough layer are in agreement with SEM and AFM results. The dispersion of the refractive index is presented in the 1-5 eV range. [DOI: 10.1002/pssc.200777818]

Sones, C. L. , Muir, A. C., Ying, Y. J. , Mailis, S., Eason, R. W. , Jungk, T., Hoffmann, Á. & Soergel, E. Precision nanoscale domain engineering of lithium niobate via UV laser induced inhibition of poling. Appl. Phys. Lett. 92, 072905 (2008).
Continuous wave ultraviolet laser irradiation at λ = 244 nm on the +z face of undoped and MgO doped congruent lithium niobate single crystals has been observed to inhibit ferroelectric domain inversion. The inhibition occurs directly beneath the illuminated regions, in a depth greater than 100 nm during subsequent electric field poling of the crystal. Domain inhibition was confirmed by both differential domain etching and piezoresponse force microscopy. This effect allows the formation of arbitrarily shaped domains in lithium niobate and forms the basis of a high spatial resolution microstructuring approach when followed by chemical etching. [DOI: 10.1063/1.2884185]