17 February 2010 Comparison of concepts for high-brightness diode lasers at 976 nm
Author Affiliations +
Abstract
Especially for fiber pump applications there is a strong demand for high-brightness diode lasers in the 10W power regime. Broad-area and tapered laser concepts seem to be the most promising candidates for high brightness, which is proportional to output power divided by beam quality. Within this talk we give a comparison of both concepts identifying the possibilities and limitations of both concepts. Whereas fast axis far fields show mostly a current independent behaviour, for broad-area lasers near- and farfields in the slow axis suffer from a strong current and temperature dependence, limiting the brightness. For tapered diode lasers the brightness is limited by the temperature characteristics of M2 and astigmatism. Therefore for both concepts it is essential to have lasers with excellent thermal management, which can be realized by 4- 5mm long resonators in combination with wall-plug efficiencies well beyond 60%. To fulfill these issues, we have realized MBE grown InGaAs/AlGaAs broad-area and tapered lasers with resonator lengths between 4mm and 5mm and 45° fast axis far field emitting at 976nm. For a 5mm long broadarea laser with 90μm stripe width a beam parameter product of less than 5.9 mm x mrad (M2<10) has been achieved at 10W with a slope efficiency of 1.1W/A and a maximum wall-plug efficiency of 65%. For a tapered laser with a taper angle of 4° and 5mm resonator length, 10W have been demonstrated with a slope efficiency of 1.05W/A and a maximum wall-plug efficiency of 56%. Beam quality is below 3 up to 8W.
© (2010) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
J. Gilly, J. Gilly, P. Friedmann, P. Friedmann, H. Kissel, H. Kissel, J. Biesenbach, J. Biesenbach, M. T. Kelemen, M. T. Kelemen, } "Comparison of concepts for high-brightness diode lasers at 976 nm", Proc. SPIE 7583, High-Power Diode Laser Technology and Applications VIII, 75830S (17 February 2010); doi: 10.1117/12.840698; https://doi.org/10.1117/12.840698
PROCEEDINGS
10 PAGES


SHARE
Back to Top