Kilowatt-class, 1-cm diode laser bars at 910-940 nm with improved power, conversion efficiency and beam quality
Advances in lateral and vertical design leading to higher power, efficiency and beam quality in 1-cm bars are presented. GaAs-based, quasi-continuous-wave, 1-cm bars using extreme-triple-asymmetric (ETAS) waveguide designs deliver increased output power and efficiency. ETAS bars with 4mm resonator and 79% fill-factor provide 1.9kW peak power (200µs, 10Hz) from a single quantum well, with 67% peak efficiency at 298K. At 203K, peak power increases to 2.26kW with 74% peak efficiency (60% at 2.0kW). Improved lateral bar layout enabled a reduced lateral divergence of 15° (95% power) at 1.9kW at 298K without sacrificing power or efficiency. Polarization purity remains above 95%.
Md. Jarez Miah received the B.Sc. degree in electrical and electronic engineering from the Bangladesh University of Engineering and Technology, Bangladesh, in 2009, the M.Sc. degree in communications technology from Ulm University, Germany, in 2012, and the doctoral degree in electrical engineering from the Technical University of Berlin, Germany, in 2017. His M.Sc. and Doctoral theses dealt with design, fabrication and characterization of vertical-cavity surface-emitting lasers, and high-power and high-brightness edge-emitting semiconductor lasers, respectively. From 2017 to 2019, he was a Senior Semiconductor Engineer with VI Systems GmbH and a Development Engineer with TRUMPF Laser GmbH, Berlin. In 2020, he joined the Ferdinand-Braun-Institut gGmbH, Leibniz-Institut für Höchstfrequenztechnik, Berlin, as a Postdoctoral Researcher. His current research focuses on the development of high-performance semiconductor diode lasers and laser bars.