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Individual points produced by airborne laser scanning (ALS) may have large variation in their accuracy, a fact that is often omitted in the subsequent derivation of digital terrain models. The accuracy of a single point is governed by three main factors: F ...
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 ...
The authors demonstrate an optically pumped surface emitting polymer dye laser fabricated by nanoimprint lithography. The laser is based on an organic dye hosted within a poly(methylmethacrylate) matrix coated on a transparent substrate, and the laser cavi ...
An instrument for high-speed laser perfusion imaging comprises a laser source, a detector, a signal-processing unit, data memory, and a screen to display the results. A section of the sample surface is illuminated with laser light; the reemitted light from ...
We combine photonic crystal and quantum cascade band engineering to create an in-plane laser at terahertz frequency. We demonstrate that such photonic crystal lasers strongly improve the performances of terahertz quantum cascade material in terms of thresh ...
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 ...
A novel laser soldering method for hermetic packaging of temperature sensitive devices such as organic electronics, micro- and nanostructures is presented in this work. The package combines a thermally optimized LTCC (Low Temperature Co-fired Ceramic) base ...
A wavelength monitor based on a pair of tilted fiber Bragg gratings is reported. The monitor exhibits a subpicometer wavelength selectivity over a broad wavelength range (> 30 nm), and a low insertion loss (< 1 dB) for laser light with polarization matchin ...
Institute of Electrical and Electronics Engineers2007
A method of separating isotopes from polyatomic molecules, in particular C from trifluoromethane HCF3, by applying to the polyatomic molecules in the gas phase infrared laser beams of different frequencies to produce multiphoton dissociation and reacti ...
Femtosecond laser irradiation has various noticeable effects on fused silica. It can locally increase the index of refraction and modify the material chemical selectivity. Regions that have been exposed to the laser are etched hundred fold faster than unex ...