The quantum-cascade laser (QCL) emitting in the mid-infrared region of 4 to 8 m has been refined to the point that its internal quantum efficiency is approaching fundamental limits. QCLs designed for power typically contain 30-40 cascades, are less than two wavelengths in width, and laser ridge lengths are typically between 3 and 6 mm. Even with state-of-the-art efficiency and thermal management, room temperature operation of such lasers is fundamentally limited to several watts. This paper describes a path to power scaling that is not fundamentally limited. Power requires volume and thermal conductance. We propose that this combination is best achieved using fewer than 15 cascades combined with broad areas. We demonstrate the first room temperature continuous-wave emission of broad-area QCLs and discuss how this scaling concept can deliver MIR emission of 10's of watts at room temperature with beam quality required for high brilliance.
W. T. Masselink, M. P. Semtsiv, Y. V. Flores, A. Aleksandrova, and J. Kischkat, "Design issues and physics for power scaling of quantum-cascade lasers," Proc. SPIE 9989, Technologies for Optical Countermeasures XIII, 99890B (Presented at SPIE Security + Defence: September 28, 2016; Published: 21 October 2016); https://doi.org/10.1117/12.2241431.
Conference Presentations are recordings of oral presentations given at SPIE conferences and published as part of the conference proceedings. They include the speaker's narration along with a video recording of the presentation slides and animations. Many conference presentations also include full-text papers. Search and browse our growing collection of more than 12,000 conference presentations, including many plenary and keynote presentations.