Work

Multivalued dispersion equation for coupling between plasmons and surface optical phonons in a graphene/polar-substrate system

Year: 2024

Type: article

Abstract: Dispersion equations are a common paradigm of collective excitation physics. However, in some systems, dispersion equations contain multivalued functions and their solutions are ambiguous. As an example, we consider graphene on a polar substrate where Dirac plasmons are coupled with surface optical phonons. The dispersion equation for this system contains square-root singularity. Using the initial value problem resolves this uncertainty and gives a unique solution. Particularly, we found that the lower plasmon-phonon mode, which in terms of dispersion can have a good quality factor, is almost absent in excitation spectra. The physical reason and experimental evidence of the mode collapse are discussed. Published by the American Physical Society 2024

Source: Physical review. B./Physical review. B

DOI: 10.1103/physrevb.110.l241403

Authors: S. M. Kukhtaruk, V. A. Kochelap

Institutions: V.E. Lashkaryov Institute of Semiconductor Physics, Institute of High Pressure Physics, Institute for High Pressure Physics

Language: English

Topic: Plasmonic and Surface Plasmon Research

Subfield: Biomedical Engineering

Field: Engineering

Domain: Physical Sciences

Open Access status: hybrid

Funders: National Research Foundation of Ukraine, National Academy of Sciences

Awards: G2814373353, G3688982180