Venting device for pressurized space suit helmet Patent

Venting device for pressurized space suit helmet to eliminate vomit expelled by crewme

Lateral coupled cavity semiconductor laser

We report the fabrication and operation of a lateral coupled cavity semiconductor laser that consists of two phase-locked parallel lasers of different lengths and with separate electrical contacts. Mode selectivity that results from the interaction between the two supermodes is investigated experimentally. Frequency selectivity and tunability are obtained by controlling the current to each laser separately. Highly stable single mode operation is also demonstrated

Frequency selectivity in laterally coupled semiconductor laser arrays

A longitudinal-mode analysis of a system of laterally coupled waveguided resonators is presented in the coupled-mode approximation. It is shown that variations in the mirror reflectivity of the individual channels result in coupling between the supermodes of the structure. This may lead to mode suppression by modulation of the threshold gain of different Fabry-Perot modes

Confocal unstable-resonator semiconductor laser

GaAs/GaAlAs heterostructure lasers with a monolithic confocal unstable resonator were demonstrated. The curved mirrors satisfying the confocal condition were fabricated by etching. Close to threshold, the lasers operate in a single lateral mode with a nearly collimated output beam. A single-lobe far-field intensity distribution as narrow as 1.90 full width at half maximum was measured

Inclusion of new LHC data in MMHT PDFs

I consider the effects of including a variety of new LHC data sets into the MMHT approach for PDF determination. I consider the impact of fitting new LHC and Tevatron data, which leads to clear improvements in some PDF uncertainties. There are specific issues with ATLAS 7 TeV jet data and I include a discussion of the treatment of correlated uncertainties and briefly the effects of NNLO corrections. I also present preliminary results with the inclusion of the high precison final ATLAS 7 TeV $W,Z$ rapidity-dependent data.Comment: 6 pages. To appear in proceedings of DIS2017 Worksho

Tilted-mirror semiconductor lasers

Broad-area GaAs heterostructure lasers with a tilted mirror were demonstrated for the first time, with the tilted mirror fabricated by etching. These lasers operate in a smooth and stable single lateral mode with a high degree of spatial coherence. The suppression of filamentation manifests itself in a high degree of reproducibility in the near-field pattern

Updates of PDFs in the MSTW framework

I present results on updates on PDFs which are obtained within the general framework which led to the MSTW2008 PDF sets. There are some theory and procedural improvements and a variety of new data sets, including many relevant up-to-date LHC data. A new set of PDFs is very close to being finalised, with no significant changes expected to the preliminary PDFs shown here.Comment: 6 pages, 6 figures,Published in PoS DIS (2014

Modal properties of unstable resonator semiconductor lasers with a lateral waveguide

The modal properties of unstable resonator lasers with a lateral waveguide have been analyzed, and an unstable resonator semiconductor laser with a real index lateral waveguide has been demonstrated. Output powers in excess of 400 mW were observed with a stable, highly coherent lateral field distribution. The incorporation of a lateral real index waveguide with the unstable resonator configuration results in an increase in the external quantum efficiency and the appearance of ripples in the lateral field distribution

Unstable resonator cavity semiconductor lasers

GaAs heterostructure lasers with unstable resonator cavities were demonstrated for the first time with both curved mirrors fabricated by etching. Typical output powers of 0.35 W were observed in a stable, highly coherent lateral mode. The laser operated stably in a single longitudinal mode over a large range of injection currents. The external quantum efficiency was 70% of that of a similar laser with both mirror facets cleaved implying good output coupling of the energy from the entire region