Options
2008
Conference Paper
Titel
Infrared semiconductor lasers for DIRCM applications
Alternative
Infrarot-Halbleiterlaserfür DIRCM Anwendungen
Abstract
We report on the development and characteristics of infrared semiconductor lasers as compact and robust light sources for Directed Infrared Countermeasures (DIRCM). The short-wavelength side of the 2-5 µm wavelength band of interest can be covered by GaSb-based optically pumped semiconductor disk lasers (OPSDLs), delivering a continuous-wave (cw) or temporally modulated multiple-Watt output with a high beam quality (M2<3). For the 3.7-5 µm wavelength range InP-based quantum cascade (QC) lasers are the best suited semiconductor laser source, delivering several hundreds of mW of average output power in a nearly diffraction limited output beam (M2<2). Further up-scaling of the output power can be achieved for OPSDLs by intra-cavity coupling of several semiconductor chips as gain elements in a multiple-disk cavity arrangement. For a 2.3 m emitting dual-disk OPSDL, a doubling of the maximum roomtemperature output power compared to that of a comparable single-chip OPSDL has been demonstrated. For QC lasers power scaling by beam-quality-preserving beam combining has been demonstrated via polarization coupling of the output beams of two individual QC lasers, yielding a coupling efficiency of 82%.
Author(s)