HOT MWIR Interband Cascade Detectors Based on Strained Layer Superlattices

The past decade has seen the development of interband cascade (IC) infrared detectors for the short-wave, mid-wave, and long-wave infrared spectral regions utilizing the versatile type-II strain layered superlattice (T2SL) material system. They have attained impressive results from pioneering work at the University of Oklahoma (OU) and the University of New Mexico (UNM) where both single element devices and focal plane arrays have been developed. Their application to the MWIR spectral region is of particular importance for their high operating temperature (HOT) potential for chemical and gas sensing, industrial monitoring, and portable spectroscopy. This presentation will highlight the recent improvements in the technology and will compare and contrast the performance of single element T2SL-IC technology with other infrared photodetector technologies such as PbSe, PbS, InGaAs, HgCdTe, and InSb based detectors with emphasis on high temperature operation in the MWIR region. Data that will be covered will include quantum efficiency, dark current, and specific detectivity. The advantages and limitations of the T2SL-IC technology will be highlighted and a pathway for improving the technology will be outlined.