Berlin 2024 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
O: Fachverband Oberflächenphysik
O 71: Poster: Plasmonics and Nanooptics
O 71.11: Poster
Mittwoch, 20. März 2024, 18:00–20:00, Poster D
Nano-imaging reveals the stacking dependent dispersion of hybrid polaritons in a Trilayer Graphene and Hexagonal Boron Nitride Heterostructure — •Christian Dittmar, Lina Jäckering, Konstantin Wirth, and Thomas Taubner — I. Institute of Physics, RWTH Aachen University
Two-dimensional (2D) van der Waals (vdW) materials can be combined to heterostructures [1]. Hexagonal Boron Nitride (hBN) and Trilayer Graphene (TLG) are two appealing 2D vdW materials. hBN is a natural hyperbolic material and enables low-loss and volume-confined hyperbolic phonon polaritons (HPhPs) [2]. TLG is gate-tuneable and hosts surface plasmon polaritons. TLG occurs in either a Bernal (ABA) or rhombohedral (ABC) stacking order [3]. Uniting isotopically pure hBN and TLG in a heterostructure enables the formation of hybridized hyperbolic plasmon-phonon polaritons (HP3). These (HP3) can be launched and imaged by a scattering-type scanning near-field optical microscope. HP3 combine the tunability of graphene and the low losses of the HPhPs in hBN. For the first time, we image stacking dependent propagating polaritons in a hBN-TLGN heterostructure. The stacking dependency manifests in the different propagation wavelength originating from different dispersions. The results lay the foundation for distinguishing different stacking orders of TLG encapsulated in hBN and for identifying domain boundaries in TLG. We also emphasize the possibility to image buried structures below an hBN layer.
[1] Basov et al. Science 354, 6309 (2016),
[2] Caldwell et al. Nature Reviews Materials 4, 552 (2019),
[3] Chen et al. Nature 487, 77 (2012)
Keywords: Graphene; hBN; Polaritons; SNOM