Colloidal Quantum Dots in Very-Long-Wave Infrared Detection: Progress, Challenges, and Opportunities

[Image: see text] The very long wave infrared (VLWIR) is an electromagnetic wave with a wavelength range of 15–30 μm, which plays an important role in missile defense and weather monitoring. This paper briefly introduces the development of intraband absorption of colloidal quantum dots (CQDs) and investigates the possibility of using CQDs to produce VLWIR detectors. We calculated the detectivity of CQDs for VLWIR. The results show that the detectivity is affected by parameters such as quantum dot size, temperature, electron relaxation time, and distance between quantum dots. The theoretical derivation results, combined with the current development status, show that the detection of VLWIR by CQDs is still in the theoretical stage.