2021/03/25 by Pawan Kumar, Jason Lynch, Baokun Song +21 · 107 citations
Engineering · Materials Science · Physics and Astronomy · #2D Materials and Applications #Absorption (acoustics) #Condensed matter physics #Coupling (piping) #Dielectric #Exciton #Materials science #Metamaterial #Nanotechnology #Optoelectronics #Perovskite Materials and Applications #Photoluminescence #Physics #Strong Light-Matter Interactions #Superlattice #cond-mat.mes-hall #cond-mat.mtrl-sci #physics.app-ph #physics.optics #van der Waals force
paper · pdf · doi:10.1038/s41565-021-01023-x
published in Nature Nanotechnology 17(2), 182-189 (Nature Portfolio) · 4 figures + supporting
arxiv created 2021/03/25 · openalex publication_date 2021/12/02 · arxiv updated 2022/03/09 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
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.