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Powerful THz radiation confined in one field period or less is an adequate tool for triggering nonlinear actions. We show results towards the realization of a tunable high-power THz source based on a laser-driven frequency conversion scheme in plasma and n ...
We theoretically and experimentally investigate a band edge Photonic Crystal (PhC) Quantum Cascade Laser (QCL) operating at 3.1 THz. The surface emission is achieved by using a second-order Bragg grating at the PhC tile boundaries. Highly directional surfa ...
We report on laser-based, high power single-cycle THz source. The THz radiation is generated by four-wave mixing in plasma and by optical rectification in organic salt crystal pumped by powerful optical parametric amplifier. The first approach permits the ...
The post-fabrication control of evanescent tunnelling in photonic crystal molecules is demonstrated through the combination of selective infiltration and oxidation. By laser non thermal oxidation, we reduce the photonic coupling by more than 30% while by m ...
The III-nitride semiconductor material system - (InAlGa)N - is of highest interest for optoelectronic applications due to its direct bandgap, tunable from the ultraviolet to the infrared spectral range. The most well-known are white light-emitting diodes, ...
Intense Terahertz radiation in organic crystals is typically generated by optical rectification of short wavelength infrared femtosecond lasers between 1.3 and 1.5 μm. In this wavelength range high energy ultrashort pump sources are hardly available. Here ...
During the past decade, various new types of organic nonlinear optical crystals have been developed to overcome the benchmark stilbazolium DAST (4-(4-(N, N-dimethylamino) styryl)-1-methylpyridinium 4-methylbenzenesulfonate) crystal. Here, we review the ace ...
We report on the experimental observation of extreme laser spectral broadening and a change in optical transmission in gallium phosphite induced by 25 MV/cm terahertz (THz) single-cycle internal field. Such intense THz radiation leads to twofold transient ...
An integrated electronic-photonic phase-locked loop (PLL) modulates the frequency of a tunable laser for use in frequency-modulated continuous-wave (FMCW) lidar 3D imaging. The proposed lidar can perform 180k range measurements per second. The rms depth pr ...
Institute of Electrical and Electronics Engineers2017
In recent years, semiconductor nanowires have attracted considerable attention as a result of their unique properties and potential applications in many fields. In particular, they can be very attractive materials for certain optoelectronic and electronic ...