High-Power High-Temperature Continuous-Wave Operation of Quantum Cascade Laser at λ∼4.6 µm without Lateral Regrowth

High-power quantum cascade lasers (λ=4.6 µm ) working in continuous wave (cw) up to 90°C are presented. The material was grown by solid-source molecular beam epitaxy and processed into narrow conventional ridge geometry without lateral regrowth. High cw output power of 850 mW at 10°C and more than 200 mW at 90°C were obtained with threshold current densities of 1.34 and 2.47 kA/cm², respectively, for a high-reflectivity-coated 12-µm -wide and 3-mm-long laser.