Suppression of Auger recombination in long-wavelength quantum well W-structure lasers

Using picosecond pulses from a free-electron laser, we have carried out a pump-probe determination of Shockley-Read-Hall (SRH) and Auger free-carrier recombination lifetimes in two long-wave (6--7 {μ}m) W-structure laser with ${InAs/Ga}_{1{-}x}{In}ₓSb/InAs/AlSb$ active regions. The SRH coefficient is nearly constant $(A{≈}4.0×{}{10}⁸{s}^{{{-}}1}),$ while the Auger coefficient has an upper limit of $C=4.0×{}{10}^{{-}27}$ to $2.2×{}{10}^{{-}27}{cm}⁶/s$ in the temperature range 40--230 K. This represents an order of magnitude Auger suppression compared to type-I III-V semiconductors with the same energy gap.