Proceedings of nanoGe Fall Meeting19 (NFM19)
DOI: https://doi.org/10.29363/nanoge.nfm.2019.032
Publication date: 18th July 2019
HgTe nanocrystals offer a unique combination of broadly tunable optical absorption in the infrared from 1 to 100 µm and photoconductive properties.
However the maturity of the current device remains far weaker what have been achieve for solar cell using PbS nanocrystals. Current limitations are the result of limited material development and poor understanding of the electronic structure of the material under colloidal form.
In this talk, I will discuss some of the recent developments relative to HgTe nanocrystal integration into photodiodes operating in the short wave and mid wave infrared. I will present how the concepts of unipolar barrier has been transferred from III-V semiconductor to colloidal HgTe nanocrystal film [1].
Another important limitation to address is tradeoff between the absorption depth (> 1 µm) and the carrier diffusion length (< 100 nm) which make that most current devices have a weak light absorption (10 % of the incident light typically). This issue can be addressed by two strategies which are the development of ink to achieve thick high mobility film [2] and by enhancing the light matter coupling thanks to the introduction of plasmonic resonator.
Finally, I would say a few words about how it is possible to take advantage of intraband transitions in self doped nanocrystal to design mid wave infrared detector [3]
