Resonator-QWIP FPA development

Abstract

Previously, we adopted the resonator-QWIPs and increased the FPA QE to 30 − 40%. In this work, we performed a systematic theoretical analysis on the potential performance based on this new detector structure. In this analysis, the doping density and the number of quantum wells are varied to obtain different detector characteristics. For 25 μm pixel pitch, 10 Me − integrated charge, and F/2 optics, the analysis shows that a 9.2 μm cutoff R-QWIP optimized for high temperature operation could provide 20 mK NEΔT at τ int = 2.6 ms when operating at T = 80 K. An R-QWIP with a 10.2 μm cutoff could achieve the same with τ int = 1.3 ms at T = 74 K. Similar NEΔT can also be achieved with smaller pixel pitch down to 6 μm for both cutoffs with a more relaxed operating condition where the f-number is 1, τ int is 5 ms, and T is 70 K. We provide preliminary test detector data to support this analysis.

Metallic cavity quantum well infrared photodetector for filter-free SF6 gas imaging

“…Furthermore, a wide range of doping concentrations (0.6-4 × 10 17 cm -3 ) could maintain the QE beyond 60% giving rise to a robustness for varying doping concentration. The regularities of the R-QWIP (Sun et al 2017;Choi et al 2015) are much different from the results of the MC-QWIP. The simulated QE of the R-QWIP (Sun et al 2017) is proportional to the doping concentration and ranges from 30% to 70% when the doping concentration increases from 0.2 × 10 18 cm -3 to 1.0 × 10 18 cm -3 .…”

“…Thus, the resonance effect is weak and the QW absorption decreases with the decreasing doping concentration while the bandwidth basically remains unchanged. This is the case of the R-QWIP (Sun et al 2017;Choi et al 2015). As to the MC-QWIP, due to the reflection on the Ti/Au side wall, the number of the light passes through the QW active layer is more than that in the R-QWIP.…”