Light-Matter Coupling in Scalable Van der Waals Superlattices

Abstract

Two-dimensional (2D) crystals have renewed opportunities in design and assembly of artificial lattices without the constraints of epitaxy. However, the lack of thickness control in exfoliated van der Waals (vdW) layers prevents realization of repeat units with high fidelity. Recent availability of uniform, wafer-scale samples permits engineering of both electronic and optical dispersions in stacks of disparate 2D layers with multiple repeating units. We present optical dispersion engineering in a superlattice structure comprised of alternating layers of 2D excitonic chalcogenides and dielectric insulators. By carefully designing the unit cell parameters, we demonstrate > 90 % narrowband absorption in < 4 nm active layer excitonic absorber medium at room temperature, concurrently with enhanced photoluminescence in cm2 samples. These superlattices show evidence of strong light-matter coupling and exciton-polariton formation with geometry-tunable coupling constants. Our results demonstrate proof of concept structures with engineered optical properties and pave the way for a broad class of scalable, designer optical metamaterials from atomically-thin layers.

4 figures + supporting

References in corpus (7)

• Anomalous Lattice Vibrations of Single and Few-Layer MoS2
• Light-emitting diodes by bandstructure engineering in van der Waals heterostructures
• Mixed-Dimensional van der Waals Heterostructures
• Strong light-matter coupling in two-dimensional atomic crystals
• Strong interlayer coupling in van der Waals heterostructures built from single-layer chalcogenides
• Infrared hyperbolic metasurface based on nanostructured van der Waals materials
• First principles modeling of exciton-polaritons in polydiacetylene chains

Cited by in corpus (17)

• Nanomaterials for Quantum Information Science and Engineering
• Roadmap for Photonics with 2D Materials
• Dielectrics for Two-Dimensional Transition Metal Dichalcogenide Applications
• Alternating superconducting and charge density wave monolayers within bulk 6R-TaS2
• Tailoring the dielectric screening in WS${}_2$-graphene heterostructures
• Tutorial: Exciton resonances for atomically-thin optics
• Wafer-scale Programmed Assembly of One-atom-thick Crystals
• Exciton Assisted Deeply Subwavelength Nano-Photonics
• Screening 0D materials for 2D nanoelectronics applications
• Near-unity light-matter interaction in mid-infrared van der Waals nanocavities
• Temperature-dependent excitonic light manipulation with atomically-thin optical elements
• Approaching the absorption limit with monolayer semiconductor superlattices
• Photonics in Flatland: Challenges and Opportunities for Nanophotonics with 2D Semiconductors
• Strongly Coupled Exciton--Hyperbolic-phonon-polariton Hybridized States in hBN-encapsulated Biased Bilayer Graphene
• Nanocavity-mediated Purcell enhancement of Er in TiO${}_2$ thin films grown via atomic layer deposition
• Optical microscope based universal parameter for identifying layer number in two-dimensional materials
• Subnanometric control of coupling between WS${}_2$ monolayers with a molecular spacer