New Study Reveals Discovery of Rydberg Moiré Excitons in Semiconductor Material
In a groundbreaking study published in Science, researchers from the Institute of Physics of the Chinese Academy of Sciences (CAS) and Wuhan University have reported the observation of Rydberg moiré excitons in the monolayer semiconductor WSe2 adjacent to small-angle twisted bilayer graphene (TBG). The findings open up new possibilities for utilizing Rydberg excitons in a wide range of applications.
Rydberg excitons are highly excited Coulomb-bound states of electron-hole pairs and have been extensively studied in various physical platforms. These excitons possess large dipole moments and strong mutual interactions, making them ideal candidates for applications in sensing, quantum optics, and quantum simulation.
However, efficiently trapping and manipulating Rydberg excitons has been a long-standing challenge. The emergence of two-dimensional moiré superlattices with tunable periodic potentials offers a potential solution. Dr. Xu Yang and his collaborators have been investigating the application of Rydberg excitons in 2D semiconducting transition metal dichalcogenides.
In their latest study, the researchers utilized low-temperature optical spectroscopy measurements and numerical calculations to study Rydberg moiré excitons in WSe2 adjacent to TBG. The optical spectra exhibited multiple energy splittings, a red shift, and a narrowed linewidth, indicating the presence of Rydberg moiré excitons. Numerical calculations attributed these observations to the spatially varying charge distribution in TBG, creating a moiré potential landscape for interacting with Rydberg excitons.
The researchers also demonstrated a novel method of manipulating Rydberg excitons using the moiré superlattice. This manipulation is typically challenging in bulk semiconductors. The tunable moiré wavelengths, in-situ electrostatic gating, and longer lifetime of the excitons enable greater controllability of the system. This controllability, coupled with the strong light-matter interaction, holds promise for applications in quantum information processing and quantum computation.
The discovery of Rydberg moiré excitons in semiconductor materials opens up new opportunities for exploring Rydberg-Rydberg interactions and coherent control of Rydberg states. The researchers foresee potential applications in various fields, including quantum information processing and quantum computation.
The study, titled “Observation of Rydberg moiré excitons,” was published in Science. The research team was led by Dr. Xu Yang from the Institute of Physics of the Chinese Academy of Sciences and Dr. Yuan Shengjun from Wuhan University.
For more information, please refer to the original research article published in Science.