Showing papers in "Optical Materials in 2005"

TL;DR: In this article, an overview of the recent results on upconversion spectroscopy obtained in our group is presented, where it is demonstrated that as much as 50% of the NIR excitation photons contribute to the up-conversion emission.

TL;DR: A review of the main phenomena related with the linear optical properties of isolated and supported metal nanoparticles is presented in this article, where extinction, absorption and scattering efficiencies are calculated using the Mie theory and the discrete dipole approximation.

TL;DR: In this article, the optical behavior of the complexes of 4-(1-methyl-1-mesitylcyclobutane-3-yl)-2-(2-hydroxy-5-methoxybenzylidenehydrazino) thiazole was investigated by optical reflectance and transmittance measurements.

TL;DR: In this article, focused ion beam (FIB) was used for patterning lithium niobate (LN) at submicronic scale by means of FIB bombardment.

TL;DR: In this article, strong visible emission under UV (320 and IR (967) excitation on ZrO 2 :Sm 3+ and Zr O 2 :Er 3+ nanophosphors were obtained and the concentration effect on the luminescence and crystalline structure was reported.

TL;DR: In this article, a two-step spray pyrolysis (SP) and citrate-gel (CG) method was used to synthesize YVO 4 :Eu phosphors from a nitrate aqueous solution with citrate acid and polyethylene glycol (PEG) as additives.

TL;DR: In this paper, a green-emitting phosphor YPO 4 :Tb used in a PDP was prepared by two different methods, i.e., conventional solid-state reaction route and solution-based co-precipitation route.

TL;DR: In this paper, the authors summarized results in the study of tetragonal disordered R3+-doped bismuth double tungstate and double molybdate ABi(XO4)2 (A = Li, Na; X = Mo, W) as well as stoichiometric LiYb(MoO 4 )2 crystals.

TL;DR: In this article, the effect of film thickness on optical properties of the Cr(III) complex having 2-pyridincarbaldehye thiosemicarbazone thin films was investigated.

TL;DR: In this article, a mixture of rare earth nitrates, orthoboric acid and an organic fuel was used for combustion to produce nanocrystalline powders requiring only a simple apparatus.

TL;DR: In this article, the effect of surfactants on the electro-optical properties of holographic polymer dispersed liquid crystal (HPDLC) Bragg gratings was studied in detail.

TL;DR: In this paper, an extensive experimental study of optical gain in silicon nanocrystals is under way, and different types of samples have been tested using different measurement techniques (e.g., variable stripe length method in Trento and in Rochester, prism coupling in Canberra) and different pump laser sources (from femtosecond to cw).

TL;DR: In this article, the effects of the Yb 3+ concentration on the structural and luminescence properties of ZrO 2 :Yb 3 + -Er 3+ nanoparticles prepared by sol-gel process are reported.

TL;DR: In this article, tuning of the optical properties is controlled by liquid crystals (LCs) that are infiltrated into the silicon matrix, and active tuning is demonstrated both out-of-plane and in-plane.

TL;DR: In this article, a solid state nonlinear optical medium is obtained by the incorporation of the metalloporphyrin, Zinc Tetra Phenyl Porphrin (ZnTPP) in Nafion polymer membrane.

TL;DR: In this article, optical spectroscopic analysis of rare earth ions in transparent oxyfluoride glass-ceramics obtained from SiO2-Al2O3-PbF2-CdF2 based precursor glasses is presented.

TL;DR: In this article, the authors showed that the technique allows formation of various periodically grooved structures with wide photonic band gaps in the middle IR spectral range suitable for microphotonic elements in a silicon chip.

TL;DR: In this article, the optical behavior of porous silicon mirrors is studied, revealing good performance in the visible wavelength range, and showing a great sensitivity to different liquids infiltrated into the porous structure.

TL;DR: In this article, a modified glycolate or sol-gel method was used to synthesize nanocrystalline yttrium aluminum garnet, Y 3 Al 5 O 12 or YAG.

TL;DR: In this paper, the effect of Ag/Er co-doped thin plates of silicate glass was investigated with the aim of assessing the effective role of silver as a sensitizer for erbium.

TL;DR: In this paper, the optical-functional properties of an integrated-optical strip-waveguide in a planar polymer chip were investigated by using a two-beam-interferometric method.

TL;DR: In this paper, the emission lines in the cathodoluminescence spectrum of the europium doped α-Al 2 O 3 sample were analyzed and it was inferred that the dopant ions occupied low symmetry sites in the host lattice.

TL;DR: In this article, an enhanced cooperative absorption and upconversion emission of Yb 3+ pairs in nanocrystalline YAGs was observed and the estimated concentration normalized ratio of maximum visible absorption to maximum IR absorption emission of 7.55 × 10 − 22 cm 3 was estimated.

TL;DR: In this paper, the optical properties of Tm 3+ doped lead-niobium-germanate glasses (GeO 2 -PbO-Nb 2 O 5 ) for different concentrations ranging between 0.5 and 3.5 wt%.

TL;DR: In this article, the authors investigated the spectroscopic properties of Er 2 O 3 -doped PbO-Ga 2O 3 -GeO 2 glasses and showed that the contribution of the migration-accelerated energy transfer among Er 3+ ions to the nonradiative transition from the 4 I 13/2 level is larger than that from 4 I 11/2 levels.

TL;DR: In this paper, the authors presented optical properties of silica-titania thin films prepared by the sol-gel technique and applied grating couplers to couple light in and out of planar waveguides.

TL;DR: In this paper, the etching behavior of sapphire has been investigated in an inductively couple plasma using Cl2, BCl3 and CH2Cl2 as the reagent.

TL;DR: Germanium nanocrystals embedded in silicon dioxide matrix were grown using rf magnetron sputtering and showed the formation of nearly spherical nanocrystal evenly distributed in the oxide matrix Annealed nanostructures exhibited strong and broad photoluminescence in the visible range at room temperature.

TL;DR: In this article, a thin films of large band gap β-In2S3−3xO3x compounds have been synthesized by annealing a multilayer structure of indium and sulphur sequentially deposited.

TL;DR: In this paper, the luminescence properties of Yb3+-doped Li6Y(BO3)3 crystalline material are presented for applications as active medium in diode pumped (short pulse) lasers emitting around 1040 nm and pumped at 975 nm.