Optical gain calculation of mid-infrared InAsN/GaSb quantum-well laser for tunable absorption spectroscopy applications

Abstract We report on optical gain calculations of a dilute-nitride mid-infrared laser structure designed to be grown on InAs substrate. The active region is composed of several strain-compensated type-II “W”-like InAsN/GaSb/InAsN quantum wells adapted to operate near 3.3 μm at room temperature. For typical injected carrier density σ  = 1.1012 cm − 2 , the theoretical laser structure performances reveal a gain value at around 1000 cm − 1 at 300 K, inducing a modal gain value equal to 50 cm − 1 . Low radiative current densities lower than 100 A/cm 2 are predicted, indicating that this dilute-nitride structure could operate at 300 K with small threshold current density.