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The light-current (L-I), spectral, and far-field characteristics of quantum cascade lasers (QCLs) with seven different wavelengths in the lambda = 4.3 to 6.3 mum ranges are reported. Simulations of a wide-stripe photonic-crystal distributed-feedback QCL is described which based on the quality is projected to emit multiple watts of continuous-wave (CW) power into a single-mode beam at T=200K.

The substantial suppression of infrared blackbody emission from HgCdTe photoiodide arrays with cutoff wavelengths of 4.8, 5.5, and 6.0 micrometer. At room temperature, a reverse bias induces internal negative luminescence efficiencies of 95%, 93%, and 88%, respectively, which correspond to apparent cooling of the surface temperatures by 60, 59, and 49K.

We demonstrate the substantial suppression of infrared (IR) blackbody emission from HgCdTe photodiode arrays with cutoff wavelengths of 4.8, 5.5, and 6.0 μm. At room temperature, a reverse bias induces internal negative luminescence (NL) efficiencies of 95%, 93%, and 88%, respectively, which correspond to apparent cooling of the surface temperatures by 60, 59, and 49 K. Reverse-bias saturation current densities for the three devices were 0.11, 0.7, and 32 A/cm2. Measurement and analysis of the material transmission characteristics indicate that the small residual inefficiencies may be limited by a parasitic absorption process. The 4.8 and 5.5 pm photodiodes were fabricated into 18 × 2 arrays with total areas of 5 mm × 5 mm. In both cases, all 36 array elements were fully operable, and had similar electrical and NL properties. Effective fill factors were ≈100%, since carrier diffusion led to the extraction of carriers from regions between the elements. These results show that efficient, low-power NL devices with active areas in the square-inch range are now feasible for such applications as the cold shielding of infrared focal-plane arrays. [ABSTRACT FROM AUTHOR]