272 research outputs found

    Decomposition of NO studied by infrared emission and CO laser absorption

    Get PDF
    A diagnostic technique for monitoring the concentration of NO using absorption of CO laser radiation was developed and applied in a study of the decomposition kinetics of NO. Simultaneous measurements of infrared emission by NO at 5.3 microns were also made to validate the laser absorption technique. The data were obtained behind incident shocks in NO-N2O-Ar (or Kr) mixtures, with temperatures in the range 2400-4100 K. Rate constants for dominant reactions were inferred from comparisons with computer simulations of the reactive flow

    Characterizing photonic crystal waveguides with an expanded k-space evanescent coupling technique

    No full text
    We demonstrate a direct, single measurement technique for characterizing the dispersion of a photonic crystal waveguide (PCWG) using a tapered fiber evanescent coupling method. A highly curved fiber taper is used to probe the Fabry-Pérot spectrum of a closed PCWG over a broad k-space range, and from this measurement the dispersive properties of the waveguide can be found. Waveguide propagation losses can also be estimated from measurements of closed waveguides with different lengths. The validity of this method is demonstrated by comparing the results obtained on a ‘W1’ PCWG in chalcogenide glass with numerical simulation

    Enhanced spontaneous emission rate from single InAs quantum dots in a photonic crystal nanocavity at telecom wavelengths

    Get PDF
    The authors demonstrate coupling at 1.3 micro m between single InAs quantum dots (QDs) and a mode of a two dimensional photonic crystal (PhC) defect cavity with a quality factor of 15 000. By spectrally tuning the cavity mode, they induce coupling with excitonic lines. They perform a time integrated and time-resolved photoluminescence and measure an eightfold increase in the spontaneous emission rate inducing a coupling efficiency of 96%. These measurements indicate the potential of single QDs in PhC cavities as efficient single-photon emitters for fiber-based quantum information processing applications. [on SciFinder (R)

    A case of the amniotic constrictions in a newborn child (Simonart syndrome)

    Get PDF
    We want to present a case of the amniotic constrictions in a newborn child. Today there are no ethiopathogenetic treatment methods for treating complications of amniotic constrictions. All available treatment methods are symptomatic and are mainly aimed at patient care. In rare cases, surgical correction of the defect is possible, sometimes even in the intrauterine period. The peculiarity of this case is late, postnatal detection of multiple malformations in a newborn child with timely observation of a pregnant woman in the women’s consultation

    Integrated liquid-core optical fibers --- ultra-efficient nonlinear liquid photonics

    Full text link
    We have developed a novel integrated platform for liquid photonics based on liquid core optical fiber (LCOF). The platform is created by fusion splicing liquid core optical fiber to standard single-mode optical fiber making it fully integrated and practical - a major challenge that has greatly hindered progress in liquid-photonic applications. As an example, we report here the realization of ultralow threshold Raman generation using an integrated CS2 filled LCOF pumped with sub-nanosecond pulses at 1064nm and 532nm. The measured energy threshold for the Stokes generation is ~ 1nJ, about three orders of magnitude lower than previously reported values in the literature for hydrogen gas. The integrated LCOF platform opens up new possibilities for ultralow power nonlinear optics such as efficient white light generation for displays, mid-IR generation, slow light generation, parametric amplification, all-optical switching and wavelength conversion using liquids that have orders of magnitude larger optical nonlinearities compared with silica glass.Comment: 4 pages, 3 figure
    corecore