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We present a comparison of theoretical calculations and experimental measurements of the Auger recombination rate in a narrow-gap semiconductor superlattice with a complex band structure. The calculations and measurements indicate that the rate depends on density as n 2 for low density, and changes to an n dependence when the electrons and holes become degenerate. The calculations are the first to incorporate superlattice umklapp processes, which contribute about half of the total rate and substantially improve the agreement with experiment.

We present calculations of the differential gain and threshold current densities for a 3.7 m multiple quantum well structure consisting of a ''well'' composed of several periods of an InAs/InGaSb superlattice alternating with a quinternary alloy ''barrier.'' We find serious limitations to the optical properties of active regions composed of these multiple quantum wells, and propose a four-layer superlattice structure which corrects these problems.

We report the characterization of a set of broad-area semiconductor diode lasers with mid-wave infrared (3–5 μm) emission wavelengths. The active region of each laser structure is a 5- or 6-period multiple quantum well (MQW) with Ga0.75In0.25As0.22Sb0.78 barriers and type-II (broken-gap) Ga0.75In0.25Sb/InAs superlattice wells. The cladding layers of each laser structure are n- and p-type InAs/AlSb (24 Å /24 Å) superlattices grown lattice-matched to a GaSb substrate. By tailoring constituent layer thicknesses in the Ga0.75In0.25Sb/InAs superlattice wells, laser emission wavelengths ranging from 3.28 μm (maximum operating temperature=170 K) to 3.90 μm (maximum operating temperature=84 K) are obtained.

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