IPG Photonics

About: IPG Photonics is a based out in . It is known for research contribution in the topics: Laser & Fiber laser. The organization has 903 authors who have published 1241 publications receiving 63339 citations.

9xx nm single emitter pumps for multi-kW systems

Abstract: High-power high-brightness multimode edge emitting pumps have been developed. Comprehensive development efforts have resulted in 3 mm-long cavity diodes with far-field divergence reduced down to 26°. Output in excess of 20W CW from 90 μm-wide aperture single emitter was demonstrated for the first time. Peak power was reached at 25A CW driving current and was limited by power supply. Peak CW power efficiency was as high as 67%. Two coolerless package types designed to operate up to 10W output and up to 20W output are reported. About 95% fiber coupling efficiency into NA<0.12 was demonstrated in the entire range of driving currents for both types of pumps. For packages of the later design efficiency over 50% is maintained up to 16W CW ex-fiber output. Diode junction overheat above heatsink temperature is less than 20°C up to ~ 18W ex-fiber output.

Improved magnetic anomalies of the Antarctic lithosphere from satellite and near-surface data

Abstract: SUMMARY The Antarctic magnetic anomaly map compiled marine and airborne surveys collected south of 60 ◦ S through 1999 and used Magsat data to help fill in the regional gaps between the surveys. Orsted and CHAMP satellite magnetic observations with greatly improved measurement accuracies and temporal and spatial coverage of the Antarctic, have now supplanted the Magsat data. We combined the new satellite observations with the near-surface survey data for an improved magnetic anomaly map of the Antarctic lithosphere. Specifically, we separated the crustal from the core and external field components in the satellite data using crustal thickness variations estimated from the terrain and the satellite-derived free-air gravity observations. Regional gaps in the near-surface surveys were then filled with predictions from crustal magnetization models that jointly satisfied the near-surface and satellite crustal anomalies. Comparisons in some of the regional gaps that also considered newly acquired aeromagnetic data demonstrated the enhanced anomaly estimation capabilities of the predictions over those from conventional minimum curvature and spherical harmonic geomagnetic field models. We also noted that the growing number of regional and world magnetic survey compilations involve coverage gaps where these procedures can contribute effective near-surface crustal anomaly estimates.

Dégazage magmatique diffus à la Soufrière de Guadeloupe, Antilles

Abstract: A soil gas profiling made along the southern basis of Soufriere summit lava dome, in Guadeloupe, reveals the existence of diffuse emanations of magma-derived CO 2 in coincidence with a major volcanic (Ty) fault, where CO 2 concentrations at 70 cm depth in the ground reach 35–96 % and are associated with a thermal convective cell. Outside, a few ‘cold’ gaseous anomalies of volcanic origin (lack of methane) provide reliable conditions for continuous radon monitoring of soil degassing.