Probing the ultimate plasmon confinement limits with a van der Waals heterostructure

TLDR

Nanophotonics requires confining light to dimensions far below its wavelength, but metal plasmonics faces a trade‑off between confinement and losses. The authors fabricated heterostructures of monolayer graphene, a single‑monolayer hexagonal boron nitride spacer, and an array of metallic rods. They achieved vertical plasmon confinement between the metal and graphene even with a one‑monolayer hBN spacer, indicating a versatile platform for nanophotonics. Alcaraz Iranzo et al., Science, this issue p.

Abstract

Light confined to a single atomic layer The development of nanophotonic technology is reliant on the ability to confine light to spatial dimensions much less than the wavelength of the light itself. Typically, however, in metal plasmonic approaches, there is a trade-off between confinement and losses. Alcaraz Iranzo et al. fabricated heterostructures comprising monolayers of graphene and hexagonal boron nitride (hBN) and an array of metallic rods. The light was confined vertically (as propagating plasmons) between the metal and the graphene, even when the insulating hBN spacer was just a single monolayer. Such heterostructures should provide a powerful and versatile platform for nanophotonics. Science , this issue p. 291