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We report the demonstration of continuous-wave interband cascade lasers (ICLs) near 13 μm. The attained lasing wavelength of 13.2 μm at 92 K stands as the longest cw emission wavelength ever reported for III-V interband lasers. This achievement is attributed to the adoption of an innovative quantum well (QW) active region comprising strained InAs0.5P0.5 layers in contrast to the commonly used “W” QW active region, showing the potential of the modified QW active region with InAsP layers in improving device performance and extending wavelength coverage of ICLs. 

We report significantly enhanced device performance in long wavelength interband cascade lasers (ICLs) by employing a recently proposed innovative quantum well (QW) active region containing strained InAsP layers. These ICLs were able to operate at wavelengths near 14.4 μm, the longest ever demonstrated for III–V interband lasers, implying great potential of ICLs to cover an even wider wavelength range. Also, by applying the aforesaid QW active region configuration on ICLs at relatively short wavelengths, ICLs were demonstrated at a low threshold current density (e.g., 13 A/cm2 at 80 K) and at temperatures up to 212 K near 12.4 μm, more than 50 K higher than the previously reported ICLs with the standard W-shape QW active region at similar wavelengths. This suggests that the QW active region with InAsP layers can be used to improve device performance at the shorter wavelengths. 

The incorporation of dilute concentrations of bismuth into traditional III–V alloys produces significant reductions in bandgap energy presenting unique opportunities in strain and bandgap engineering. However, the disparity between the ideal growth conditions for the host matrix and those required for substitutional bismuth incorporation has caused the material quality of these III–V–Bi alloys to lag behind that of conventional III–V semiconductors. InSb1−xBix, while experimentally underexplored, is a promising candidate for high-quality III–V–Bi alloys due to the relatively similar ideal growth temperatures for InSb and III–Bi materials. By identifying a highly kinetically limited growth regime, we demonstrate the growth of high-quality InSb1−xBix by molecular beam epitaxy. X-ray diffraction and Rutherford backscattering spectrometry (RBS) measurements of the alloy's bismuth concentration, coupled with smooth surface morphologies as measured by atomic force microscopy, suggest unity-sticking bismuth incorporation for a range of bismuth concentrations from 0.8% to 1.5% as measured by RBS. In addition, the first photoluminescence was observed from InSb1−xBix and demonstrated wavelength extension up to 7.6 μm at 230 K, with a bismuth-induced bandgap reduction of ∼29 meV/% Bi. Furthermore, we report the temperature dependence of the bandgap of InSb1−xBix and observed behavior consistent with that of a traditional III–V alloy. The results presented highlight the potential of InSb1−xBix as an alternative emerging candidate for accessing the longwave-infrared. 

We demonstrate a monolithic all-epitaxial resonant-cavity architecture for long-wave infrared photodetectors with substrate-side illumination. An nBn detector with an ultra-thin (t≈350 nm) absorber layer is integrated into a leaky resonant cavity, formed using semi-transparent highly doped (n++) epitaxial layers, and aligned to the anti-node of the cavity's standing wave. The devices are characterized electrically and optically and demonstrate an external quantum efficiency of ∼25% at T=180 K in an architecture compatible with focal plane array configurations. 

III–V semiconductor type-II superlattices (T2SLs) are a promising material system with the potential to significantly reduce the dark current of, and thus realize high-performance in, infrared photodetectors at elevated temperatures. However, T2SLs have struggled to meet the performance metrics set by the long-standing infrared detector material of choice, HgCdTe. Recently, epitaxial plasmonic detector architectures have demonstrated T2SL detector performance comparable to HgCdTe in the 77–195 K temperature range. Here, we demonstrate a high operating temperature plasmonic T2SL detector architecture with high-performance operation at temperatures accessible with two-stage thermoelectric coolers. Specifically, we demonstrate long-wave infrared plasmonic detectors operating at temperatures as high as 230 K while maintaining dark currents below the “Rule 07” heuristic. At a detector operating temperature of 230 K, we realize 22.8% external quantum efficiency in a detector absorber only 372 nm thick ([Formula: see text]) with a peak specific detectivity of 2.29 × 10⁹cm Hz^1∕2W⁻¹at 9.6  μm, well above commercial detectors at the same operating temperature.