Midinfrared luminescence imaging and its application to the optimization of light-emitting diodes

Midinfrared luminescence imaging spectroscopy is used for evaluating surface structures etched into narrow-gap PbSe films. These structures provide a luminescence enhancement by a factor of 6. On the basis of such structures an optically pumped luminescence device is realized. A maximum cw output power of 0.5 mW and a slope efficiency of 0.2mW∕A are obtained at 25 °C. The power efficiency amounts to 2.3×10−2%. The emission wavelength is 4.2 μm, with a half width of 0.8 μm (50 meV). Such devices are promising light sources for a new generation of gas detection systems.