High Performance Quantum Cascade Laser Frequency Combs At Lambda Similar To 6 Mu M

We present efficient quantum cascade laser frequency combs at 6 mu m, operating from -20 degrees C to 50 degrees C, with a maximum total (two facets) output power of 520 mW. The dispersion of the waveguide is carefully engineered with the help of plasmonic-waveguide method to achieve efficient comb operation. 3mm, 4.5 mm and 6 mm-long devices were tested with various ridge-widths (from 2.8 mu m to 5.5 mu m). All the devices showed comb operation at all measured temperatures proving the reliability of the plasmonic-waveguide method. (C) 2020 The Author(s)