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We report a new and more precise Sellmeier equation obtained by using the analysis of quasi-phase-matching curves of the optical parametric generation (OPG) in 1D periodically poled LiTaO3 (1D-PPLT) of different grating periods.

We report a new and more precise Sellmeier equation obtained by using the analysis of quasi-phase-matching curves of the optical parametric generation (OPG) in 1D periodically poled LiTaO3 (1D-PPLT) of different grating periods. [ABSTRACT FROM AUTHOR]

We report a new and more precise Sellmeier equation derived using the quasi-phase-matching curves obtained from the study of the optical parametric generation (OPG) in 1D periodically poled LiTaO3 (1D-PPLT) of different periods at low and high pump power.

In this work, we experimentally and theoretically investigate the optical and electrical optimization of an OLED associated to a mixed-order DFB cavity. We, firstly focus on the design and the fabrication of a mixed-order DFB cavity with a high quality factor. We particularly study the impact of the deposition of the organic layers on the topology and the quality factor of the cavity.

Simultaneous oscillation of two pairs of signals and idlers was demonstrated. We also showed the efficiency of the sum frequency generation of two idlers was comparable with second harmonic generation of each idler. Our design shows the potential of building multi-wavelength laser source from UV to NIR on monolithic crystal.

We report the influence of Ag nanoparticle arrays on the emission properties of organic light emitting diodes (OLED). First, we studied the features of Ag arrays related to the periodicity. The obtained results emphasize the existence of two coupling regimes dominated by near or far field effects, respectively. Thereafter, we studied the influence of these gratings on the performances of OLED devices. Our results reveal the benefit of the plasmonic structures which allow a precise tuning of the OLED properties.

In this work, we demonstrate that it is possible to obtain an optical parametric oscillator with a simultaneous amplification of multiple frequencies using only a nonlinear photonic crystal with highly polished end-faces, preventing the utilization of external cavity mirrors.

We report the first study of optical planar and channel waveguides fabricated in the new nonlinear crystal [Ca.sub.4]YO[(B[O.sub.3]).sub.3] by use of MeV He+-implantations. The [n.sub.x], [n.sub.y], and [n.sub.z] refractive index modifications are studied. Losses in nonannealed YCOB waveguides measured with a CCD camera are found to be less than 2 dB [cm.sup.-1]. This work is the first step toward the investigation of frequency conversion within the obtained guiding structures. OCIS codes: 230.3120, 230.7380, 230.4320.

The mechanism for inscription of electric-arc-induced long-period gratings in SMF28 fiber was studied. The refractive-index profiles of irradiated fiber samples were measured, and their structures were investigated by Raman and luminescence spectroscopy. Slight geometrical deformations of the irradiated fiber were measured. A significant change in the Raman spectrum range from 200 to 700 [cm.sup.-1] caused by the electric arc is reported. The results show a decrease in the intensity of this band, indicating a modification, such as densification, of the glass structure. No modification of the fictive temperature was measured. A large increase in the red luminescence band was also observed and attests to the creation of defects in the fiber network structure. OCIS codes: 060.2340, 300.6450, 160.2290.

Nd,Tm:YAG codoped single crystal waveguides were studied in order to discover if the presence of Nd3+ ions favors blue luminescence at 486 nm. Innovative implantation techniques were applied to locally change Δn and form varied H+ implanted channel structures in Nd,Tm:YAG buried epitaxial waveguiding layers. The guided blue luminescence due to the Tm3+ 1G4→3H6 transition was studied under infrared excitation at 785 nm (Tm3+ absorption) and 808 nm (Nd3+ absorption) for the epitaxial planar waveguides of different Tm3+ and Nd3+ concentrations for all the implanted channel waveguide structures. [ABSTRACT FROM AUTHOR]

Crystalline rare-earth-doped yttrium oxide thin films were grown by pulsed-laser deposition (PLD) on SiO[SUB2]/Si substrates. The structural and morphological features of these films were studied, as a function of the growth conditions (temperature from 200 to 800 °C and oxygen pressure from 10[SUP-6] to 0.5 mbar), by using Rutherford backscattering spectroscopy, x-ray diffraction, and atomic force microscopy. The related optical properties were investigated by m-lines spectroscopy at 633 nm and 1.3 μm. The optimal conditions were found to be a temperature and a pressure of 700 °C and 10[SUP-6] mbar, respectively. In that case, the Y[SUB2]O[SUB3] films are stoichiometric with controlled erbium and europium rates, and present a well-crystallized, (111) textured cubic phase and a low surface roughness of about 10 Å. Moreover, the PLD films show good waveguiding properties with a high refractive index (1.92 at 633 nm), a step-index structure, and low optical losses around 1 dB/cm in the near infrared region, promising for a planar amplifier function. [ABSTRACT FROM AUTHOR]

The feasibility of producing channel waveguides in crystalline layers of YAG:Tm,Nd, epitaxially deposited on YAG crystals is explored. The guided blue luminescence is studied under infrared excitation at 785 nm ([Tm.sup.3+] absorption) and 808 nm ([Nd.sup.3+] absorption) for the epitaxial planar waveguides of different [Tm.sup.3+] and [Nd.sup.3+] concentrations for all the implanted channel waveguide structures.

A study was conducted, using Rutherford backscattering spectroscopy, x-ray diffraction, and atomic force microscopy, to investigate the structural and morphological features of crystalline rare-earth-doped yttrium oxide thin films grown by pulsed-laser deposition (PLD) on SiO2/Si substrates. The result confirms that the PLD of rare-earth-doped yttria at high temperature and low pressure leads to the growth of good quality thin films with a polycrystalline structure and a low-surface roughness.