We have generated picosecond opfic1 pulses with very pure spectral characteristics using semiconductor lasers with monolithic cavities. Fx repetition rates less than 10 GHz, gain-switching of DFB lasers with quantum well loss-gratings is usul. Monolithic colliding pulse mode-locked semiconductor lasers are used to generate short pulses with repetition rate up to 350GHz.

A new technique for modelling the dynamic spectral characteristics of DFB semiconductor lasers above threshold, which is based on the transmission-line laser model, is described. This includes the effects of index carrier dependence and longitudinal index variations. The timedomain responses and spectra of quarter-wave shifted grating devices are compared with unshifted devices under transient ...

Sensitive photoacoustic detection of methane (CH4), hydrogen chloride (HCl) and water vapour (H2O) in the near-infrared range using semiconductor DFB lasers is reported. A detection limit of 0.17 ppm of CH4, 0.2 ppm of HCl and 0.024 ppm of H2O (signal-to-noise ratio = 3) is reached using a properly designed photoacoustic cell operating in its first longitudinal mode.

We numerically optimise in-span signal power asymmetry in different advanced Raman amplification schemes, achieving a 3% asymmetry over 62 km SMF using random DFB Raman laser amplifier. We then evaluate the impact of such asymmetry on the performance of systems using mid-link OPC by simulating transmission of 7 × 15 Gbaud 16QAM Nyquist-spaced WDM-PDM signals.

We have identified a family of highly selective allosteric modulators of the group I metabotropic glutamate receptor subtype 5 (mGluR5). This family of closely related analogs exerts a spectrum of effects, ranging from positive to negative allosteric modulation, and includes compounds that do not themselves modulate mGluR5 agonist activity but rather prevent other family members from exerting t...

  A novel compact fiber-coupled NIR system based on a DFB diode laser source is employed as a portable and sensitive gas sensor for trace detection of combustion pollutant molecules. We demonstrate the performance of such an NIR gas sensor by tracing the absorption lines of CO and CH4 using 2f-WMS technique at moderate temperature of T ~ 600°C in the recuperator channel of an industrial furnace...

We propose and demonstrate a cost-effective half- duplex transceiver for Fiber-to-the-Room (FTTR) network by using homemade uncooled isolator-free distributed feedback (DFB) laser as both receiver (Rx) transmitter (Tx). AlGaInAs multiple quantum wells (MQWs) partially corrugated grating are utilized operation of the DFB lasers. Tx/Rx mode switching is implemented specially designed complementar...

Using traditional Chinese medicine residue biomass as the raw material and industrial limestone a carbon absorbent, this paper investigates production of hydrogen-rich synthesis gas in pilot-scale calcium looping dual fluidized bed (DFB) system. The study focuses on analyzing distribution characteristics temperature pressure, well operation control methods DFB effects reaction temperature, laye...