Plasmon dynamics in monolayer and bilayer graphene
Plasmon are collective oscillations of mobile electrons with dynamics controlled by their charge stiffness("Drude weight"). Using terahertz spacetime metrology, we probe Plasmon dynamics of mono- and bi-layer graphene. In both systems, the experimentally measured Drude weight systematically exceeds the prediction based on non-interacting electronic system. The relative enhancement increases as the carrier density decreases. We attribute the observed deviation to the interplay of interactions and wave function structure of the Dirac fermions in multi-layer graphene. Our results establish that pseudospin structure of the single-particle electronic wave function can directly influence collective excitations, with implications that extend beyond graphene to a broad class of quantum materials.
Authors
- Yinming Shao (ORCID: https://orcid.org/0000-0002-2891-0028)
- Tobias Stauber (ORCID: https://orcid.org/0000-0003-0983-2420)
- Julian Ingham (ORCID: https://orcid.org/0000-0002-7733-9833)
- Raquel Queiroz (ORCID: https://orcid.org/0000-0002-6714-8857)
- Milan Delor (ORCID: https://orcid.org/0000-0002-9480-9235)
- D. N. Basov (ORCID: https://orcid.org/0000-0001-9785-5387)
- Nishchhal Verma (ORCID: https://orcid.org/0000-0003-2685-9879)
- Rocco A. Vitalone (ORCID: https://orcid.org/0000-0002-9009-4092)
- Cory R. Dean (ORCID: https://orcid.org/0000-0003-2967-5960)
- Brian Vermilyea (ORCID: https://orcid.org/0009-0004-1332-5485)
- Suheng Xu (ORCID: https://orcid.org/0000-0002-1456-5489)
- Birui Yang (ORCID: https://orcid.org/0009-0000-2346-8173)
- Andrew J. Millis (ORCID: https://orcid.org/0000-0001-9413-6344)
- M. M. Fogler (ORCID: https://orcid.org/0000-0001-8239-7221)
- Ran Jing
- Mengkun Liu
- Miguel Sánchez Sánchez
- Angel Rubio (ORCID: https://orcid.org/0000-0003-2060-3151)
Publication Details
- Journal
- Physical Review Letters
- Published
- 2026-11-02
- DOI
- https://doi.org/10.1103/1cdm-9rx7
- Citations
- 1
- Primary Topic
- Plasmonic and Surface Plasmon Research
- Type
- article
- Field-Weighted Citation Impact
- 1.56
Funders
- U.S. Department of Energy
- Office of Science
- Basic Energy Sciences