High-power spatial singlemode quantum cascade lasers at 8.9 µm

High performance of InP-based quantum cascade lasers emitting at λ≃9 µm is reported. A thick electroplated gold layer was deposited on top of the laser to improve heat dissipation. Devices with one facet high reflection coated produce a maximum output power of 175 mW at 40% duty cycle at room temperature and continuous-wave operation up to 278 K.