2.3-2.7-μm room temperature CW operation of InGaAsSb-AlGaAsSb broad waveguide SCH-QW diode lasers

A new approach in the design of (Al)InGaAsSb-GaSb quantum-well separate confinement heterostructure (QW-SCH) diode lasers has led to continuous-wave (CW) room-temperature lasing up to 2.7 μm. This has been achieved by using quasiternary heavily strained InGaSb(As) QW's inside a broad-waveguide SCH laser structure. The QW compositions are chosen in the region outside the miscibility gap and, as a consequence, do not suffer from clustering and composition inhomogeneity normally found with quaternary InGaAsSb compounds of 2.3-2.7-μm spectral range. Very low threshold current density (/spl sim/300 A/cm
²
) and high CW output powers (>100 mW) were obtained from devices operating in the 2.3-2.6-μm wavelength range.