Controlled Interlayer Exciton Ionization in an Electrostatic Trap in Atomically Thin Heterostructures
arXiv:2311.12941 · doi:10.1038/s41467-024-51128-9
Abstract
Atomically thin semiconductor heterostructures provide a two-dimensional (2D) device platform for creating high densities of cold, controllable excitons. Interlayer excitons (IEs), bound electrons and holes localized to separate 2D quantum well layers, have permanent out-of-plane dipole moments and long lifetimes, allowing their spatial distribution to be tuned on demand. Here, we employ electrostatic gates to trap IEs and control their density. By electrically modulating the IE Stark shift, electron-hole pair concentrations above cm can be achieved. At this high IE density, we observe an exponentially increasing linewidth broadening indicative of an IE ionization transition, independent of the trap depth. This runaway threshold remains constant at low temperatures, but increases above 20 K, consistent with the quantum dissociation of a degenerate IE gas. Our demonstration of the IE ionization in a tunable electrostatic trap represents an important step towards the realization of dipolar exciton condensates in solid-state optoelectronic devices.
14 pages, 4 main figures, 1 extended data figure
References in corpus (8)
- Observation of Long-Lived Interlayer Excitons in Monolayer MoSe2-WSe2 Heterostructures
- Evidence of high-temperature exciton condensation in 2D atomic double layers
- High-temperature superfluidity with indirect excitons in van der Waals heterostructures
- Upconverted electroluminescence via Auger scattering of interlayer excitons in van der Waals heterostructures
- Predicting the Ionization Threshold for Carriers in Excited Semiconductors
- Exciton-Mott Physics in Two-Dimensional Electron-Hole Systems: Phase Diagram and Single-Particle Spectra
- Perfect Coulomb drag in a dipolar excitonic insulator
- Perfect Coulomb drag and exciton transport in an excitonic insulator