Metal–Dielectric Mirror Coatings for 4–5-μm Quantum-Cascade Lasers

Abstract: We report the results of a comparison of metal–dielectric mirror coatings for mid-IR quantum-cascade lasers (QCLs). Samples of QCLs with Al2O3/Ti/Au and SiO2/Ti/Au optical coatings are fabricated and their characteristics are studied. It is shown that the use of metal–dielectric mirror coatings allows the output optical power of devices to be increased up to 93% and their threshold currents to be reduced by 1.25 times. © Allerton Press, Inc. 2023. ISSN 1068-3356, Bulletin of the Lebedev Physics Institute, 2023, Vol. 50, Suppl. 12, pp. S1356–S1360. Allerton Press, Inc., 2023. Russian Text The Author(s), 2023, published in Kvantovaya Elektronika, 2023, Vol. 53, No. 8, pp. 641–644.