2020/02/24 by Yanhao Tang, Jie Gu, Tang, Yanhao +13 · 2 citations
Engineering · Materials Science · Physics and Astronomy · #2D Materials and Applications #Biexciton #Condensed matter physics #Electron #Exciton #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Materials science #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Optics #Optoelectronics #Perovskite Materials and Applications #Physics #Quantum mechanics #Quantum well #Semiconductor #Strong Light-Matter Interactions #Superlattice #Wurtzite crystal structure #cond-mat.mes-hall #cond-mat.mtrl-sci #van der Waals force
paper · pdf · doi:10.48550/arxiv.2002.10067
published in arXiv (Cornell University) (Cornell University) · 16 pages, 8 figures
arxiv created 2020/02/24 · openalex publication_date 2020/02/24 · arxiv updated 2020/02/25 · openalex created_date 2020/07/23 · openalex updated_date 2026/07/28
Moiré superlattices open an unprecedented opportunity for tailoring interactions between quantum particles and their coupling to electromagnetic fields. Strong superlattice potential generates moiré minibands of excitons -- bound pairs of electrons and holes that reside either in a single layer (intralayer excitons) or two separate layers (interlayer excitons). The twist-angle-controlled interlayer hybridization of carriers can also mix the two types of excitons to combine the strengths of both. Here, we report a direct observation of spatially mixed moiré excitons in angle-aligned WSe2/WS2 and MoSe2/WS2 superlattices by optical reflectance spectroscopy. The strongly interacting interlayer and intralayer moiré excitons in WSe2/WS2 manifest energy level anticrossing and oscillator strength redistribution under a vertical electric field. We also observe doping-dependent exciton miniband renormalization and mixing near half filling of the first electron miniband of WS2. Our findings have significant implications for emerging correlated states in two-dimensional semiconductors, such as exciton condensates and Bose-Hubbard models, and optoelectronic applications of these materials.