Room temperature quantum cascade laser with similar to 31% wall-plug efficiency

In this article, we report the demonstration of a quantum cascade laser emitting at lambda approximate to 4.9 mu m with a wall-plug efficiency of similar to 31% and an output power of similar to 23 W in pulsed operation at room temperature with 50 cascade stages (N-s). With proper fabrication and packaging, this buried ridge quantum cascade laser with a cavity length of 5 mm delivers more than similar to 15 W output power, and its wall-plug efficiency exceeds similar to 20% at 100 degrees C. The experimental results of the lasers are well in agreement with the numerical predictions. (c) 2020 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).