Infrared imaging allows to visualize electromagnetic radiation beyond the visible range, in the long-wavelength domain. It is relevant for a broad range of applications, from defense to automation, food processing and chemical sensing. Current high performance solutions for SWIR, MWIR and LWIR imaging rely either on complex and expensive epitaxial structures (InGaAs on InP, HgCdTe on CZT...) or on thermal detectors (bolometers) suffering from very low temporal bandwidth. Colloidal semiconductor nanocrystals with tunable absorption in the infrared range allow the design of a new generation of cheap, solution-processable infrared detectors.

Pics:

(TOP) Two generations of cryostats built during my PhD to investigate the performance of single pixel MWIR detectors based on HgTe and HgSe nanocrystals.

(MIDDLE) Absorption spectra of interband HgTe (red), intraband HgSe (blue) and intraband HgTe (green) ranging from SWIR to FIR.

(BOTTOM) Imaging with infrared CQD. Left: SWIR image obtained with a HgTe/CMOS hybrid detector (see https://pubs.acs.org/doi/abs/10.1021/acs.chemrev.0c01120). Right: MWIR image of the tip of a soldering iron with a scanning HgSe/HgTe single-pixel device (see https://www.nature.com/articles/s41467-019-10170-8)