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The authors report a direct measurement of the optical phonon intersubband hole relaxation time in a SiGe heterostructure and a quantitative determination of hole relaxation under electrically active conditions. The results were obtained by femtosecond res ...
Characteristics of one-cascade (1.06 double right arrow 1.24 mum) and two-cascade (1.06 double right arrow 1.24 double right arrow 1.48 mum) phosphorus-doped fiber Raman lasers are studied. The cavities of both lasers are formed by Bragg gratings written d ...
An ammonia traces analyser based on photoacoustic spectroscopy is described. The system uses a CO2 laser and a properly designed resonant photoacoustic cell to achieve ammonia detection at sub-parts-per- billion (ppb) level. The instrument features unatten ...
We demonstrate an electrically-tuned nematic liquid crystal (LC) infiltrated photonic crystal (PC) laser. The PC laser is encased between two transparent indium tin oxide (ITO) glass plates which serve as the modulating electrodes and also define the LC ce ...
First investigations of photoacoustic (PA) spectroscopy (PAS) of methane using an antimonide semiconductor laser are reported. The laser fabrication is made in two steps. The structure is firstly grown by molecular beam epitaxy, then a metallic distributed ...
In this paper, we present a novel Brillouin fiber-ring laser utilizing an unbalanced Mach-Zehnder interferometer (UMZI) as coupling device. The laser is pumped by a distributed-feedback laser diode and shows continuous-wave and single-frequency operation. ...
Because of the strong electron-phonon coupling of the emitting 3d orbital in transition-metal (TM) ions, 3d systems exhibit luminescence with typically several hundred nm of spectral bandwidth. TM-ion-doped materials are, therefore, of high interest for ap ...
Spectroscopic measurements on ethylene were performed using a quasi-room-temperature quantum cascade (QC) laser operated in pulsed mode in the 10.3 μm range. Using transmission spectroscopy, a broadening of the ethylene absorption spectrum was observed wit ...
The launch of molecules from liquid surfaces in a time of flight mass spectrometer has been investigated using different sample preparation techniques, and by exposing the liquid samples to two different laser wavelengths, 337 nm from a N2 ultraviolet lase ...
We report on the fabrication of Ti:sapphire channel waveguides. Such channel waveguides are of interest, e.g., as low-threshold tunable lasers. We investigated several structuring methods including ion beam implantation followed by wet chemical etching str ...
