Chemical Physics and Dynamics of Surfaces – 2D materials – Mixed dimentionalities Van der Waals heterostructure

Team

  • Permanent members: Emmanuel Lhuillier, Yoann Prado, Hervé Cruguel

Beyond graphene and transition metal dichalcogenides (TMDC) assembly into stack of 2D material, a key benefit of 2D atomically thin material is their ability to be functionalized by capping molecule and nanoparticle to form the so, called mixed dimensionalities Van der Waals 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 were relying on the high carrier mobility of the 2D materials, such 2D system offer many additional possibilities such as optical transparency, work function tunability and transparency to field induced back gate.

For example, we have designed 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 infrared absorbing HgTe nanocrystals. We have shown that graphene electrodes enable a new mode of operation compared to metallic electrodes. It leads to a pn junction formation which favour the charge dissociation in the infrared absorbing layer.

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

 

Collaborations

  • C2N (Abdelkarim Ouerghi)
  • IPMCS (Jean Francois Dayen)

 

Funding

  • ERC Black QD
  • Project ANR Graskop and Copin

 

Transversal topic

  • Quantum confinement and 2D systems

 

Publications
  • Charlie Gréboval, Ulrich Nguétchuissi Noumbé, Audrey Chu, Yoann Prado, Adrien Khalili, et al.. Gate Tunable Vertical Geometry Phototransistor based on Infrared HgTe Nanocrystals. Applied Physics Letters, American Institute of Physics, 2020, 117 (25), pp.251104. ⟨10.1063/5.0032622⟩. ⟨hal-03086952⟩
  • Ulrich Nguétchuissi Noumbé, Charlie Gréboval, Clément Livache, Audrey Chu, Hicham Majjad, et al.. Reconfigurable 2D/0D p-n Graphene/HgTe Nanocrystal Heterostructure for Infrared Detection. ACS Nano, American Chemical Society, 2020, ⟨10.1021/acsnano.0c00103⟩. ⟨hal-02526080⟩
  • Ulrich Nguétchuissi Noumbé, Charlie Gréboval, Clément Livache, Thibault Brulé, Bernard Doudin, et al.. Ionic Glass–Gated 2D Material–Based Phototransistor: MoSe 2 over LaF 3 as Case Study. Advanced Functional Materials, Wiley, 2019, 29 (33), pp.1902723. ⟨10.1002/adfm.201902723⟩. ⟨hal-02272351⟩
  • Hugo Henck, Debora Pierucci, Julien Chaste, Carl H. Naylor, Jose Avila, et al.. Electrolytic phototransistor based on graphene-MoS 2 van der Waals p-n heterojunction with tunable photoresponse. Applied Physics Letters, American Institute of Physics, 2016, 109 (11), pp.113103. ⟨10.1063/1.4962551⟩. ⟨hal-01438654⟩