Photodetectors operating at low voltages, in the spectral band from near ultraviolet to near infrared, ultra-fast (10ns) and highly sensitive, find applications in many areas, from Aerospace to Security, Cultural Heritage and Green Economy. However, on the market such photodetectors, obtained by superimposing a Si-based and a InGaAs-based photodetector, have a response in the microsecond time scale and are very expensive. FOTONICS changes the paradigm and aims to realize and optimize a photodetector based on the ultrafast Bi2Se3/Si heterojunction, operating at low voltage from ultraviolet to infrared, with sensitivity higher than 1A/W and cheaper than those on the market. FOTONICS will exploit the properties of silicon and the innovative properties of Bi₂Se₃ nanometric films that absorb radiation from ultraviolet to infrared and exhibit a very high surface mobility. The films of Bi₂Se₃ are in fact topological insulators, namely semiconductor materials with an energy gap between 0.3 and 0.8 eV which present on the surface electronic bands with linear dispersion forming Dirac cones, as in the case of graphene.

Call: POR FESR Lazio 2014-2020 - "Progetti di Gruppi di Ricerca 2020”. Project A0375-2020-36600.
Project duration: 2 years (15/04/2021 - 15/04/2023)
Coordinator: Prof. Paola Castrucci (Dip. Fisica – Università di Roma Tor Vergata)
ISM-CNR Unit Coordinator: Daniele Catone
Other ISM-CNR participants: Stefano Turchini, Patrick O’Keeffe
Funding: 143.397,93 €