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We present photonic crystal structures that exhibit small group velocity of light, which can be used as compact optical delay component. We experimentally measure the group velocity reduction to be less than 0.008c. By breaking the rotation symmetry of the ...
We demonstrate a compact laser source suitable for trapping and cooling potassium. By frequency doubling a fiber laser diode at 1534nm in a waveguide, we produce 767nm laser light. A current modulation of the diode allows us to generate the two required fr ...
The alignment stability is a major concern for Thomson scattering systems. Even small angular deviations of the laser beams crossing the plasma lead to a loss of the calibration resulting in unreliable measurements of the electron density profile. For the ...
We demonstrate an optofluidic evanescent laser based on a solid circular distributed feedback grating with the dye solution acting as the cladding layer. The laser mode is confined within the grating and experiences optical gain via the interaction between ...
With the arrival of mode locking for Q-switched lasers to generate ultra short light pulses, a method to measure their expected time duration in the psec range was needed. A novel method, based on an intensity correlation measurement using optical second h ...
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 ...
Real- and momentum-space spectrally resolved images of microcavity polariton emission in the regime of condensation are investigated under nonresonant excitation using a laser source with reduced intensity fluctuations on the time scale of the exciton life ...
A novel magnetic actuated polymer optical platform is integrated into lamellar grating and Michelson type Fourier transform spectrometers. The proposed advantages of the novel platform over existing approaches, such as MEMS spectrometers, or bulky FTIR sys ...
The conception and realisation of a prototype 355nm wind lidar return signal simulator capable of simulating the Rayleigh and the Mie return signals is described. The system is based on a commercial dual wavelength 1064nm/532nm diode pumped solid state las ...
A theoretical description of photoacoustic spectroscopy generated by wavelength modulation of a semiconductor laser source is reported for a Lorentzian absorption line. This model describes the first- and second-harmonic photoacoustic signals produced by a ...
