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We demonstrate a new type of laser composed of an array of coupled photonic crystal nanocavities that enables high differential quantum efficiency and output power, together with a low threshold power comparable to those of single photonic crystal cavity l ...
We describe a low-power continuous-wave laser system for water-vapour sensing applications in the 935-nm region. The system is based on extended-cavity diode lasers and distributed-feedback lasers and delivers four single-mode frequency-stabilised optical ...
A new and compact photoacoustic sensor for trace gas detection in the 2-2.5 μm atmospheric window is reported. Both the development of antimonide-based DFB lasers with singlemode emission in this spectral range and a novel design of photoacoustic cell adap ...
We designed a new laser composed of two-dimensional coupled photonic crystal microcavity arrays. In these structures we have observed single mode lasing with power conversion efficiency 10 times better than a single microcavity laser. ...
Undoped fluoride glass slides have been exposed to pulsed 193-nm ultraviolet (UV) irradiation. Their absorption changes have been measured to evaluate UV-induced index changes using Kramers-Kronig relation. A layer-peeling polishing technique was applied t ...
Fiber lasers are compact lightsources with high intrinsic beam quality and high efficiency. The lasing spectrum ranges from the blue to the near infrared and is achievable using fibers with different dopants and glass compositions. All-fiber lasers are cha ...
An electrically tuned nematic liquid crystal (LC) infiltrated photonic crystal (PC) laser was analyzed. LC tuning of the PC laser was demonstrated by recording the lasing wavelength as a function of the voltage applied across the LC cell. The PC laser betw ...
We report direct absorption spectroscopic detection of ozone at ambient pressure with a pulsed, DFB quantum-cascade laser (QCL) tuned within 1044-1050 cm(-1) by temperature scanning. Wavelength calibration curves were derived from FTIR and CO2 spectra and ...
We present a detailed theoretical study of a vertical-cavity surface-emitting laser (VCSEL) with two optically coupled, active cavities. The study is based on a rate-equation model written for carriers and photons under steady-state conditions. The model a ...
Multi-hydrogenated compounds detection based on photoacoustic (PA) spectroscopy is reported. Three near-infrared semiconductor lasers are used with a resonant PA cell operated in its first longitudinal mode to monitor methane, water vapour and hydrogen chl ...
