Decomposition of NO studied by infrared emission and CO laser absorption

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

Time-resolved and antibunching experiments on single quantum dots at 1300 nm

We present time integrated and time-resolved photoluminescence (PL) measurements on a single InAs/GaAs quantum dot (QD), embedded in a planar microcavity, emitting in the 1300 nm telecom band. The results of both measurements clearly identify the exciton and biexciton transitions from a single QD. By optimizing the extn. efficiency of the QD PL into the single mode fibers and carefully tuning two InGaAs avalanche photodiodes, we were able to measure the second order correlation function with integration times comparable to those made with silicon based technol. These measurements demonstrate that our single QDs are efficient sources of triggered single photons for quantum key distribution in the O band. [on SciFinder (R)

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

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

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)

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