2008 4th International Conference on Advanced Optoelectronics and Lasers

It is well known that successful and constructive solving of a problem is essentially depends on the used tools. For example, Hermite-Gauss beams are convenient for a physical problems with rectangular symmetry, and Laguerre-Gauss beams are preferable for the problems with a rotational symmetry. Another way is the usage of coherent states. It is turned out that the coherent states are very effecti... View full abstract»

In order to increasing the number of pump beam passes from active medium, we have used an optical cavity for pumping the solid state thin disk laser which results in getting high power laser output. We analytically analyzed the necessary conditions for our design. The spot size of pumping on the active medium is controlled by distances between quasi-cavity and gain medium and mirrors (or curvature... View full abstract»

A stable guest-host system was prepared to improve the nonlinear optical (NLO) effects as well as the mechanical and morphological properties of the polymeric host matrices. A hybrid organic-inorganic nano composite synthesized via the sol-gel process in our previous work and Disperse Red 1 (DR1) was utilized as the host and the guest, respectively. Thin films were deposited on glass slides using ... View full abstract»

The ways to improve the efficiency of light field transformations by dynamic holograms with the use of the frequency-nondegenerate multiwave-mixing schemes in linearly absorbing media are analyzed. The mechanism associated with the development of the fifth-order nonlinearities in pure and colored organic liquids due to the thermooptical coefficient nonlinearity as well as due to the temperature de... View full abstract»

Nonlinear diffraction of nanosecond Nd:YAG laser and femtosecond Ti:sapphire laser radiations is investigated in random nonlinear media based on strontium tetraborate. The spectrum of reciprocal vectors of superlattice contributing to nonlinear diffraction at given angles is measured in the region from 3 to 14 mum^-1. Spectral and angular dependencies of random quasi phase ma... View full abstract»

The room-temperature intracavity difference-frequency generation in mid-infrared spectral range have been observed in a butt-joint GaAs/InGaAs/InGaP quantum-well laser diode which supports lasing at two closely spaced wavelengths in the near-infrared range. A special asymmetric waveguide design and a low-doped substrate that minimize mid infrared losses and realize phase matching condition for the... View full abstract»

The difference frequency generation arising by mixing of two near-infrared modes in a GaAs based butt-joint diode laser with germanium substrate are studied theoretically. It is shown that the power of the difference mode in the 5 - 50 THz range generated by 1-W near-infrared modes in a 100-mum-wide laser at room temperature can be 40 muW. View full abstract»

We obtain, for the first time to our knowledge, the room-temperature intracavity difference-frequency generation in the mid-infrared range (around 10 mum wavelength) in a butt-joint GaAs/InGaAs/InGaP quantum-well dual-wavelength laser diode which supports lasing at two closely spaced wavelengths in the near-infrared range close to 1 mum. We employ a special asymmetric waveguide design (which makes... View full abstract»

In this work we present the formation of dark photonic lattices in negative nonlinear medium. Bright periodic lattices are generated by interference technique and propagated through 1 cm of length of nonlinear medium (R6G with acetone). The dependence with the laser (Ar) power and the geometry selected are showed. Three very interesting cases were obtained: two dimensional dark photonic lattices (... View full abstract»

In this paper we drive a numerical model, based on physical principles, for asymmetric multiple quantum well (AMQW) lasers, as one of the key elements of optical communication systems. AMQW lasers can exhibit broad net gain profile for improved wavelength tuning. The spectra and gain characteristics were investigated for an AMQW laser with two wide and two narrow QWs. The physical effects of carri... View full abstract»

The procedure of electric-discharge XeCl-lasers modeling is presented. Although there are many reports on the different models of XeCl-lasers, for an analysis having clear physical sense it is useful to have a general procedure. In general case program of XeCl-Lasers modeling includes the next subprograms: the subprogram for solution of Boltzmann equation for electrons; subprogram for calculation ... View full abstract»

The results of experimental research of noble gas halide excilamp, using inductive high-frequency discharge, are presented. Advantage of this excilamp consists in simplicity of its design. As a source of excitation the power supply unit of own construction was used at pulse repetition frequency 10,5 MHz. Average power of energy deposition in the active medium changed from 40 up to 160 W. At an opt... View full abstract»

It is demonstrated experimentally that amplitudes of defect modes of one-dimensional photonic crystal have maximal value near edges of the photonic band gap while at the centre of the stop-band they are reduced, moreover than more number of layers in photonic crystal, the less the amplitude of defect mode at the center of the PBG. We explain such behavior of defect modes presence of losses at prop... View full abstract»

Nano-technologies of advanced photonic crystals (PCs) and quantum dots (QDs) for all-optical flip-flop (PC-FF) integrated circuits have been reviewed. Topology optimization design of high-performance PC waveguides and selective-area-growth of optical nonlinear QDs with high-uniformity/density were established for demonstration of the PC-FF. The results will pave the way for implementation of innov... View full abstract»

A novel method of local tissue oxygenation based on laser-induced in vivo photodissociation of oxyhemoglobin in cutaneous blood vessels is proposed. Dependents the value of additional oxygen extraction from oxyhemoglobin on the laser wavelength, irradiation time and the oxygen diffusion in different tissues are shown. The results of experimental study and computer modeling the kinetics of tissue o... View full abstract»

We review the phenomena of splitting and regeneration of light fields inside self-imaging planar and rectangular waveguides. We describe several applications of the phenomena in the design of novel low-loss resonators with quasi-Gaussian output. We end by proposing several designs of fiber-coupled dual-mode waveguide interferometers that can give rise to ultra-small sub-wavelength fringe spacings. View full abstract»

Interest in chalcogenide glasses for photonic applications has been growing vigorously, driven by the wide wavelength range of optical transparency, high linear refractive indices, large optical non-linearity and the possibility for hosting active rare earth dopants. In this paper some emerging technologies for the fabrication of planar chalcogenide glass waveguides and photonic devices are discus... View full abstract»

We present calculations concerning the generation of terahertz waves by difference frequency generation (DFG) using mid-infrared (MIR) radiation. We investigate phase matching conditions using a waveguide design for semiconductor materials like GaAs, GaP, InP or InAs which are transparent for both MIR and THz radiation and exhibit a large nonlinear coefficient. View full abstract»

Two-photon transitions between the perturbed 6s² ¹S₀ ground state and the perturbed 5d7s³D₂ state of a Ba atom have been experimentally investigated with different perturbing and exciting radiations. A strong dependence of the probability of two-photon transitions between these pertur... View full abstract»

Summary form only given. Silicon carbide nanocrystal films have been synthesized by new original technique of direct ion deposition. Composition and structure of bonds between carbon and silicon atoms have been studied by means of photo-electron spectroscopy using XPS-800 Kratos spectrometer with MgK radiation. The spectra have been calibrated using data obtained for bond energies for reference Si... View full abstract»

Nonlinear optical properties are investigated in novel materials based on metal alkanoate lyotropic ionic liquid crystals (ILC) matrix and ionic smectic glasses with dye and electrochromic impurities. The dynamic holographic grating is recorded under action of a laser pulse of nanosecond duration. The transient nonlinear mechanisms are consider both theoretically and experimentally, namely, (i) ab... View full abstract»

In this paper we investigate an analytical-numerical approach to the modelling of the lasing modes of a periodic open optical resonator. The resonator is an infinite chain of dielectric circular cylindrical quantum wires standing in free space, with negative imaginary part of refractive index. The lasing eigenvalue problem is reduced to a determinantal characteristic equation for the frequencies a... View full abstract»

We analyse the effects of gain and loss on the group velocity of light propagating in microring resonator chains. These are shown to permit the nonlinear all-optical control of the transmission delay in ring resonator microstructures. In the superluminal regime, the analysis of lossy structures provides a general framework for the description of faster-than-light optical signal transmission of nar... View full abstract»