Twist-angle engineering of excitonic quantum interference and optical nonlinearities in stacked 2D semiconductors

Kai-Qiang Lin (), Paulo E. Faria Junior, Jonas M. Bauer, Bo Peng, Bartomeu Monserrat, Martin Gmitra, Jaroslav Fabian, Sebastian Bange and John M. Lupton ()
Additional contact information
Kai-Qiang Lin: University of Regensburg
Paulo E. Faria Junior: University of Regensburg
Jonas M. Bauer: University of Regensburg
Bo Peng: University of Cambridge
Bartomeu Monserrat: University of Cambridge
Martin Gmitra: Pavol Jozef Šafárik University
Jaroslav Fabian: University of Regensburg
Sebastian Bange: University of Regensburg
John M. Lupton: University of Regensburg

Nature Communications, 2021, vol. 12, issue 1, 1-7

Abstract: Abstract Twist-engineering of the electronic structure in van-der-Waals layered materials relies predominantly on band hybridization between layers. Band-edge states in transition-metal-dichalcogenide semiconductors are localized around the metal atoms at the center of the three-atom layer and are therefore not particularly susceptible to twisting. Here, we report that high-lying excitons in bilayer WSe2 can be tuned over 235 meV by twisting, with a twist-angle susceptibility of 8.1 meV/°, an order of magnitude larger than that of the band-edge A-exciton. This tunability arises because the electronic states associated with upper conduction bands delocalize into the chalcogenide atoms. The effect gives control over excitonic quantum interference, revealed in selective activation and deactivation of electromagnetically induced transparency (EIT) in second-harmonic generation. Such a degree of freedom does not exist in conventional dilute atomic-gas systems, where EIT was originally established, and allows us to shape the frequency dependence, i.e., the dispersion, of the optical nonlinearity.

Date: 2021
References: Add references at CitEc
Citations: View citations in EconPapers (1)

Downloads: (external link)
https://www.nature.com/articles/s41467-021-21547-z Abstract (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:nat:natcom:v:12:y:2021:i:1:d:10.1038_s41467-021-21547-z

Ordering information: This journal article can be ordered from
https://www.nature.com/ncomms/

DOI: 10.1038/s41467-021-21547-z

Access Statistics for this article

Nature Communications is currently edited by Nathalie Le Bot, Enda Bergin and Fiona Gillespie

More articles in Nature Communications from Nature
Bibliographic data for series maintained by Sonal Shukla () and Springer Nature Abstracting and Indexing ().