Scientific article
Open access

Design of van der Waals interfaces for broad-spectrum optoelectronics

Published inNature Materials
Publication date2020

Van der Waals (vdW) materials offer new ways to assemble artificial electronic media with properties controlled at the design stage, by combining atomically defined layers into interfaces and heterostructures. Their potential for optoelectronics stems from the possibility to tailor the spectral response over a broad range by exploiting interlayer transitions between different compounds with an appropriate band-edge alignment. For the interlayer transitions to be radiative, however, a serious challenge comes from details of the materials --such as lattice mismatch or even a small misalignment of the constituent layers-- that can drastically suppress the electron-photon coupling. The problem was evidenced in recent studies of heterostructures of monolayer transition metal dichalcogenides, whose band edges are located at the K-point of reciprocal space. Here we demonstrate experimentally that the solution to the interlayer coupling problem is to engineer type-II interfaces by assembling atomically thin crystals that have the bottom of the conduction band and the top of the valence band at the Γ-point, thus avoiding any momentum mismatch. We find that this type of vdW interfaces exhibits radiative optical transition irrespective of lattice constant, rotational/translational alignment of the two layers, or whether the constituent materials are direct or indirect gap semiconductors. The result, which is robust and of general validity, drastically broadens the scope of future optoelectronics device applications based on 2D materials

  • Van der Waals heterostructures
  • Optoelectronics
  • 2D materials
  • Transition Metal Dichalcogenides
  • Excitons
Research group
  • Swiss National Science Foundation - Division II, Ambizione
  • Autre - Graphene Flagship
Citation (ISO format)
UBRIG, Nicolas et al. Design of van der Waals interfaces for broad-spectrum optoelectronics. In: Nature Materials, 2020. doi: 10.1038/s41563-019-0601-3
Main files (2)
Article (Accepted version)
Article (Accepted version)
ISSN of the journal1476-1122

Technical informations

Creation02/05/2020 11:09:00 PM
First validation02/05/2020 11:09:00 PM
Update time03/15/2023 9:08:33 PM
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