Tunable Long Wavelength ( $\sim$2.8 $\mu$m) GaInAsSb–GaSb Quantum-Well Binary Superimposed Grating Lasers

GaInAsSb-GaSb quantum-well diode lasers emitting around 2.80 μm with a single device tuning range of 60 nm are presented. This was achieved by the implementation of binary superimposed metal gratings. The lasers work at room temperature in continuous-wave mode and show tunable single-mode emission with a sidemode suppression ratio of more than 30 dB. The optical output power of more than 1 mW makes them suitable for gas sensing.