Keynote Speech

“Maximizing efficiency, power and beam quality in GaAs-based broad area edge emitters, as an enabler for emerging high-power applications”

Speaker:

Dr. Paul Crump

Ferdinand-Braun-Institut gGmbH (FBH), Berlin, Germany

Biography:

Paul Crump (Senior Member, IEEE) received the B.A. (Hons.) degree in natural science (physics) from Oxford University, Oxford, U.K., and the doctoral degree in physics from Nottingham University, Nottingham, U.K., in 1992 and 1996, respectively. His thesis dealt with experimental studies of 2D electrical transport effects in semiconductor heterostructures. From 1996 to 2001, he was with Agilent Technologies Corporation, Ipswich, U.K., where he helped develop high-performance single- mode InP-based laser diodes. In 2001, he joined nLight Photonics Corporation, Vancouver, WA, USA, where he helped develop high-power, high-efficiency GaAs, and InP-based broad-area diode lasers and bars. In 2007, he joined the Ferdinand-Braun-Institut gGmbH, Leibniz-Institut für Höchst- frequenztechnik, Berlin, Germany, where he leads the High-Power Diode Laser Lab, that performs applied research into high performance broad-area diode lasers and modules. He served as the chair of the IEEE Photonics Globalization Committee from 2021-2023, is a senior editor for the IEEE Photonics Journal, and serves currently on the committees of the IEEE Photonics Conference (Sub- topic: Light Sources) and SPIE Conference High Power Diode Laser Technology Conference, after terms as chair of the Semiconductor Lasers sub-committee at CLEO USA (2022-2023) and as general chair of the International Semiconductor Laser Conference in 2021 in Potsdam, Germany.

Abstract:

GaAs-based high-power diode lasers play a crucial enabling role in many critical established and emerging industrial applications, from the world’s largest laser market, laser material processing, via the rapidly growing additive manufacturing field, through to wholly new fields of development such as the generation of secondary sources of radiation up to power generation via laser-induced fusion. A simultaneous rapid scaling in performance, addition of new functions and a reduction in costs in €/W is needed to support these developments. An overview of progress in the field is presented, illustrated using case studies from FBH research and technology development programs. Examples include efforts to scale power and efficiency around the 940 nm wavelength range, from collaborative research in diode physics to identify and overcome power bottlenecks (e.g. rapid local carrier-loss driven by spatial hole burning), to device technology efforts for higher per-component power, recently enabling the first 90 W single emitter with conversion efficiency of over 70% and 1900 W single diode laser bar. In a further example, progress in diode-laser-, assembly- and optical-techniques is enabling innovative kilowatt direct-diode laser modules operating at 780 nm wavelength to be produced, for use in the rapid and efficient construction of complex aluminium-based structures in restricted environments, as needed for emerging applications in light engineering in the transport sector. In addition, high-power pulsed diode laser pumps that operate with very high repetition rates at high powers are in strong demand and in rapid development as an enabling technology for high-energy pulsed solid-state lasers, for use in generating secondary sources of radiation, as well as for trials in power generation via laser-based fusion. Recent progress here includes the demonstration of fiber-coupled kilowatt 780 nm modules at high duty cycles as a pump for multi-joule Tm:YAG crystals.