title: Enhanced Light-Matter Interaction in Graphene/h-BN van der Waals Heterostructures.
abstract: By investigating the optoelectronic properties of prototypical graphene/hexagonal boron nitride (h-BN) heterostructures, we demonstrate how a nanostructured combination of these materials can lead to a dramatic enhancement of light-matter interaction and give rise to unique excitations. In the framework of ab initio many-body perturbation theory, we show that such heterostructures absorb light over a broad frequency range, from the near-infrared to the ultraviolet (UV), and that each spectral region is characterized by a specific type of excitations. Delocalized electron-hole pairs in graphene dominate the low-energy part of the spectrum, while strongly bound electron-hole pairs in h-BN are preserved in the near-UV. Besides these features, characteristic of the pristine constituents, charge-transfer excitations appear across the visible region. Remarkably, the spatial distribution of the electron and the hole can be selectively tuned by modulating the stacking arrangement of the individual building blocks. Our results open up unprecedented perspectives in view of designing van der Waals heterostructures with tailored optoelectronic features.
authors.affiliation: Institut für Physik and IRIS Adlershof, Humboldt-Universität zu Berlin , 12489 Berlin, Germany.|Laboratoire de Physique Théorique, Faculté des Science Exactes, Université de Bejaia , 06000 Bejaia, Algeria.
authors.forename: Wahib
authors.initials: W
authors.lastname: Aggoune
authors.affiliation: Institut für Physik and IRIS Adlershof, Humboldt-Universität zu Berlin , 12489 Berlin, Germany.
authors.forename: Caterina
authors.identifier: http://orcid.org/0000-0002-9243-9461
authors.initials: C
authors.lastname: Cocchi
authors.affiliation: Institut für Physik and IRIS Adlershof, Humboldt-Universität zu Berlin , 12489 Berlin, Germany.
authors.forename: Dmitrii
authors.initials: D
authors.lastname: Nabok
authors.affiliation: Laboratoire de Physique Théorique, Faculté des Science Exactes, Université de Bejaia , 06000 Bejaia, Algeria.
authors.forename: Karim
authors.initials: K
authors.lastname: Rezouali
authors.affiliation: Laboratoire de Physique Théorique, Faculté des Science Exactes, Université de Bejaia , 06000 Bejaia, Algeria.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Akli Belkhir
authors.affiliation: Institut für Physik and IRIS Adlershof, Humboldt-Universität zu Berlin , 12489 Berlin, Germany.
authors.forename: Claudia
authors.identifier: http://orcid.org/0000-0003-3523-6657
authors.initials: C
authors.lastname: Draxl