A theoretical study of laser structures based on dilute-nitride InAsN for mid-infrared operation
New dilute-nitride InAsN/GaSb laser diodes on an InAs substrate with a 'W' or 'M' design are theoretically investigated using a ten-band k ⋅ p model including valence, conduction and nitrogen-induced bands. For these laser diodes, designed to operate at 3.3 µm at room temperature, optical transition matrix elements for TE and TM modes between the valence sub-bands and the conduction sub-bands, modal gain and total threshold current densities are calculated. Under the hypothesis of a total loss coefficient α = 50 cm−1, non-conventional 'W' and 'M' multiquantum well laser structures present a calculated threshold current density Jth lower than 1.1 kA cm−2.