Surface plasmon polaritons in a topological insulator embedded in an optical cavity

Journal Article · Mon Mar 17 00:00:00 EDT 2014 · Applied Physics Letters

DOI:https://doi.org/10.1063/1.4869228· OSTI ID:22257821

Li, L. L., E-mail: [e-mail] ^[1]; Xu, W., E-mail: [e-mail] ^[1]; Department of Physics, Yunnan University, Kunming 650091 ^[2]

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1. Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031 (China)
2. (China)

Very recently, the surface plasmons in a topological insulator (TI) have been experimentally observed by exciting these collective modes with polarized light [P. Di Pietro, M. Ortolani, O. Limaj, A. Di Gaspare, V. Giliberti, F. Giorgianni, M. Brahlek, N. Bansal, N. Koirala, S. Oh, P. Calvani, and S. Lupi, Nat. Nanotechnol. 8, 556 (2013)]. Motivated by this experimental work, here we present a theoretical study on the surface plasmon polaritons (SPPs) induced by plasmon-photon interactions in a TI thin film embedded in an optical cavity. It is found that the frequencies of SPP modes are within the terahertz (THz) bandwidth and can be tuned effectively by adjusting the surface electron density and/or the optical cavity length. Since the surface electron density can be well controlled by the gate-voltage applied perpendicular to the TI surface, our theoretical results indicate that gated TI thin films may have potential applications in the electrically tunable THz plasmonic devices.

• OSTI ID: 22257821
• Journal Information: Applied Physics Letters, Vol. 104, Issue 11; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ELECTRON DENSITY
PHOTONS
PLASMONS
POLARONS
SURFACES
THIN FILMS
TOPOLOGY