1.1. Synthesis of narrow band gap and semimetal nanocrystals

The group is working on the synthesis of narrow band gap and semimetal nanoparticles. We in particular take benefit from intraband transitions in the IR as a new design path for colloidal heterostructure

Left : Tem image of nanocrystal. Right Infrared spectra of doped nanocrystals

associated publications :

• Terahertz HgTe nanocrystals : beyond confinement, N. Goubet, A. Jagtap, C. Livache, B. Martinez, H. Portales, X. Zhen Xu, R.P.S.M. Lobo, B. Dubertret, E. Lhuillier, J. Am. Chem. Soc. 140, 5033(2018).
• Near to Long Wave Infrared Mercury Chalcogenide Nanocrystals from Liquid Mercury, N. Goubet, M. Thomas, C. Gréboval, A. Chu, J. Qu, P. Rastogi, S.-S. Chee, M ; Goyal, Y. Zhang, X. Z. Xu, G. Cabailh, S. Ithurria, E. Lhuillier, J Phys Chem C (2020)

The library of nanocrystal from the team

1.2. Infrared colloidal optoelectronic

We use these narrow band gap nanomaterials to develop the next generation of low cost infrared detector. We have interst in develloping new concept of detector with enhanced light matter coupling and also to push the applied side with demonstration of focal plane array which active layer is made of infrared nanocrystals

Associated publications :

• A Colloidal Quantum Dot Infrared Photodetector and its use for Intraband Detection, C. Livache, B. Martinez, N. Goubet, C. Greboval, J. Qu, A. Chu, S. Royer, S. Ithurria, M. G. Silly, B. Dubertret, E. Lhuillier, Nature Comm 10, 2125 (2019).
• Potential of Colloidal Quantum Dot based Solar Cell for Near-Infrared Active Imaging, J. Ramade, J. Qu, A. Chu, C. Gréboval, C. Livache, N. Goubet, B. Martinez, G. Vincent, E. Lhuillier, ACS Phot 7, 272 (2020)
• Near Unity Absorption in Nanocrystal Based Short Wave infrared Photodetector using Guided Mode Resonator, A. Chu, C. Gréboval, N. Goubet, B. Martinez, C. Livache, P. Rastogi, F. Bresciani, Y. Prado, S. Suffit, S. Ithurria, G. Vincent, E. Lhuillier, ACS Photonics 6, 10, 2553-2561 (2019)

some images of devices made in the team

The field effect transistor has become the most versatile strategy to study the transport properties of nanocrystal film. The goal is to overcome conventional gating through thin dielectric such as SiO2 which is conventionally used, but present some drawbacks such as a large leakage or limited carrier density modulation (<1013cm-2). This part of the research activity aims to develop new gating methods able to achieve large carrier density, low temperature operability in particular using electrolyte gating

Left scheme of an electrolytic transistor where the channel is based on nanocrystals. Right : Transistor transfer curve

Associated publications :

• Field effect transistor and photo transistor of narrow band gap nanocrystal arrays using ionic glasses, C. Gréboval, U. Noumbe, N. Goubet, C. Livache, J. Ramade, J. Qu, A. Chu, B. Martinez, Y. Prado, S. Ithurria, A. Ouerghi, H. Aubin, J.-F. Dayen, E. Lhuillier, Nano Lett 19, (2019)
• Investigating the n and p type electrolytic charging of colloidal nanoplatelets, E.Lhuillier, S. Ithurria, A. Descamps-Mandine, T. Douillard, R. Castaing, X.Z. Xu, P-L. Taberna, P. Simon, H. Aubin, B. Dubertret, J Phys Chem C 119, 21795 (2015).

3.1. 2D nanocrystals

We have a long term experience with 2D nanocrystals, the so-called nanoplatelets. Here we work on the investigation of their electronic and their devices (LED, detector) integration

scheme of a CdSe NPL based LED which is used coupled to a PbS nanocrystal based solar cell to design an all nanocrystal based communication setup

Associated publication : *. A nanoplatelet-based light emitting diode and its use for all-nanocrystal LiFi-like communication, J. Qu, P. Rastogi, C. Gréboval, C. Livache, M. Dufour, A. Chu, S.-S. Chee, J. Ramade, X. Z. Xu, S. Ithurria, E. Lhuillier, ACS Appl Mater Interfaces (2020).

3.2. mixed dimentionalities Van der waals heterostructures

The group has also interest in designing mixed dimentionalities Van der waals heterostructures combining 2D material (graphene, TMDC) and nanocrystals

scheme of a device combining graphene based electrodes, HgTe nanocrystals for IR absorption and LaF3 ionic gate for high capacitance

Associated publications :

• Ionic glass gated 2D material based fast phototransistor : MoSe2 over LaF3 as case study, U. Noumbe, C. Gréboval, C. Livache, T. Brule, B. Doudin, A. Ouerghi, E. Lhuillier, J.-F. Dayen, Adv Func Mat (2019).
• Reconfigurable 2D/0D p-n Graphene/HgTe nanocrystal heterostructure for Infrared detection, U. N. Noumbé, C. Gréboval, C. Livache, A. Chu, H. Majjad, L. E. Parra López, L. D. Notemgnou Mouafo, B. Doudin, S. Berciaud, J. Chaste, A. Ouerghi, E. Lhuillier, J.-F. Dayen, ACS Nano (2020)

ERC Starting grant : project blackQD : 2018-2022

DGA : PhD funding - 2018-2021

ANR : Porject frontal, Copin, Graskop and IPER-Nano2

Labex Matisse : PhD grant - 2016-2019

C Nano grant dopQD. (2016-2017)

ANR : grant H2DH (2015-2019).