Ultraviolet interlayer excitons in bilayer WSe2

Research output: Contribution to journalResearch articleContributedpeer-review


  • Kai Qiang Lin - , Xiamen University, University of Regensburg (Author)
  • Paulo E. Faria Junior - , University of Regensburg (Author)
  • Ruven Hübner - , University of Bremen (Author)
  • Jonas D. Ziegler - , Chair of Ultrafast Microscopy and Photonics (ct.qmat) (Author)
  • Jonas M. Bauer - , University of Regensburg (Author)
  • Fabian Buchner - , University of Regensburg (Author)
  • Matthias Florian - , University of Michigan, Ann Arbor (Author)
  • Felix Hofmann - , University of Regensburg (Author)
  • Kenji Watanabe - , National Institute for Materials Science Tsukuba (Author)
  • Takashi Taniguchi - , National Institute for Materials Science Tsukuba (Author)
  • Jaroslav Fabian - , University of Regensburg (Author)
  • Alexander Steinhoff - , University of Bremen (Author)
  • Alexey Chernikov - , Chair of Ultrafast Microscopy and Photonics (ct.qmat), Clusters of Excellence ct.qmat: Complexity and Topology in Quantum Matter (Author)
  • Sebastian Bange - , University of Regensburg (Author)
  • John M. Lupton - , University of Regensburg (Author)


Interlayer excitons in van der Waals heterostructures are fascinating for applications like exciton condensation, excitonic devices and moiré-induced quantum emitters. The study of these charge-transfer states has almost exclusively focused on band edges, limiting the spectral region to the near-infrared regime. Here we explore the above-gap analogues of interlayer excitons in bilayer WSe2 and identify both neutral and charged species emitting in the ultraviolet. Even though the transitions occur far above the band edge, the states remain metastable, exhibiting linewidths as narrow as 1.8 meV. These interlayer high-lying excitations have switchable dipole orientations and hence show prominent Stark splitting. The positive and negative interlayer high-lying trions exhibit significant binding energies of 20–30 meV, allowing for a broad tunability of transitions via electric fields and electrostatic doping. The Stark splitting of these trions serves as a highly accurate, built-in sensor for measuring interlayer electric field strengths, which are exceedingly difficult to quantify otherwise. Such excitonic complexes are further sensitive to the interlayer twist angle and offer opportunities to explore emergent moiré physics under electrical control. Our findings more than double the accessible energy range for applications based on interlayer excitons.


Original languageEnglish
Pages (from-to)196-201
Number of pages6
JournalNature nanotechnology
Issue number2
Publication statusPublished - Feb 2024

External IDs

PubMed 38049597