Coupling Interlayer Excitons to Whispering Gallery Modes in van der Waals Heterostructures
Ronja Khelifa, Patrick Back, Nikolaus Flöry, Shadi Nashashibi, Konstantin Malchow, Takashi Taniguchi, Kenji Watanabe, Achint Jain, Lukáš Novotný
Abstract
heterobilayer between two slabs of h-BN and directly pattern the resulting stack into waveguide-coupled disk resonators. This enables us to position the active materials into regions of highest optical field intensity, thereby maximizing the mode overlap and the coupling strength. Since the interlayer exciton emission energy is lower than the optical band gaps of the individual monolayers and since the interlayer transition itself has a weak oscillator strength, the circulating light is only weakly reabsorbed, which results in an unaffected quality factor. Our devices are fully waveguide-coupled and represent a promising platform for on-chip van der Waals photonics.