Controlled interlayer exciton ionization in an electrostatic trap in atomically thin heterostructures
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 2 × 10<sup>12</sup> cm<sup>-2</sup> 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.
Authors
- Andrey Sushko (ORCID: https://orcid.org/0000-0002-2756-9753)
- Giovanni Scuri (ORCID: https://orcid.org/0000-0003-1050-3114)
- James Hone (ORCID: https://orcid.org/0000-0002-8084-3301)
- Andrés M. Mier Valdivia (ORCID: https://orcid.org/0000-0003-1656-9501)
- Bumho Kim (ORCID: https://orcid.org/0000-0002-5671-5641)
- Kateryna Pistunova (ORCID: https://orcid.org/0000-0002-3170-1657)
- Philip Kim (ORCID: https://orcid.org/0000-0002-8255-0086)
- Takashi Taniguchi (ORCID: https://orcid.org/0000-0002-1467-3105)
- Kenji Watanabe (ORCID: https://orcid.org/0000-0003-3701-8119)
- Andrew Y. Joe (ORCID: https://orcid.org/0000-0003-4376-7386)
- You Zhou (ORCID: https://orcid.org/0000-0002-9854-545X)
- Kristiaan De Greve (ORCID: https://orcid.org/0000-0002-1314-9715)
- Mikhail D. Lukin (ORCID: https://orcid.org/0000-0002-8658-1007)
- Luis A. Jauregui (ORCID: https://orcid.org/0000-0002-7813-8005)
- Hongkun Park (ORCID: https://orcid.org/0000-0001-9576-8829)
- Dapeng Ding
Institutions
- University of California, Riverside (US)
- Harvard University (US)
- University of California, Irvine (US)
- National Institute for Materials Science (JP)
- Harvard University Press (US)
- University of Maryland, College Park (US)
- Columbia University (US)
- Stanford University (US)
Publication Details
- Journal
- Nature Communications
- Published
- 2024-08-08
- DOI
- https://doi.org/10.1038/s41467-024-51128-9
- Citations
- 11
- Primary Topic
- 2D Materials and Applications
- Type
- article
- Field-Weighted Citation Impact
- 1.29
Funders
- Ministry of Education, Culture, Sports, Science and Technology
- Samsung
- Multidisciplinary University Research Initiative
- Japan Society for the Promotion of Science
- Office of Naval Research
- Air Force Office of Scientific Research