Institut des
NanoSciences de Paris
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Mixed dimentionalities Van der Waals heterostructure

Emmanuel Lhuillier

Beyond graphene and transition metal dichalcogenides (TMDC) assembly into stack of 2D material, a key benefit of 2D atomically thin material is their hability to be functionlized by capping molecule and nanoparticle to form the so, called mixed dimentionalities Van der waal heterostructure

Here, we explore the coupling of 2D materials such as graphene and TMDC with narrow band-gap nanocrystals to design optically active system in the infrared. While most of part effort for the use of 2D material where relying on the high carrier mobility of the 2D materials, such 2D system offer many additional posibilities such as optical transparency, work function tunability and transparency to field induced back gate. For example, we have design a phototransistor combining a superionic gate made of LaF3, functionalized by graphene as work function tunable electrodes and on top of which the channel is made of IR absorbing HgTe nanocrystals. We have shown that graphene electrodes enable a new mode of operation compared to metallic electrodes. The graphene enables a new operation mode for the device where pn jyuction is formed which favor the charge dissociation if the IR absorbing layer

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Left : Figure Left scheme of a hybrid graphene HgTe heterostructure. Right phase diagram of the hybrid heterostructure revealing the formation of a pn junction


Related publications

- Reconfigurable 2D/0D p–n Graphene/HgTe Nanocrystal Heterostructure for Infrared Detection, UN Noumbé et al, ACS nano 14, 4567-4576 (2020)
- Ionic Glass–Gated 2D Material–Based Phototransistor : MoSe2 over LaF3 as Case Study, UN Noumbé et al, Advanced Functional Materials 29, 1902723 (2019)
- Electrolytic phototransistor based on graphene-MoS2 van der Waals p-n heterojunction with tunable photoresponse, H Henck et al, Applied Physics Letters 109, 113103 (2017)


Main collaborations

- C2N - Abdelkarim Ouerghi
- IPMCS – Jean Francois Dayen