Abstract
Metal and dielectric have long been thought as two different states of
matter possessing highly contrasting electric and optical properties. A
metal is a material highly reflective to electromagnetic waves for
frequencies up to the optical region. In contrast, a dielectric is
transparent to electromagnetic waves. These two different classical
electrodynamic properties are distinguished by different signs of the real
part of permittivity: The metal has a negative sign while the dielectric has
a positive one. Here, we propose a different topological understanding of
metal and dielectric. By considering metal and dielectric as just two
limiting cases of a periodic metal–dielectric layered metamaterial, from
which a metal can continuously transform into a dielectric by varying the
metal filling ratio from 1 to 0, we further demonstrate the abrupt change of
a topological invariant at a certain point during this transition,
classifying the metamaterials into metallic state and dielectric state. The
topological phase transition from the metallic state to the dielectric state
occurs when the filling ratio is one-half. These two states generalize our
previous understanding of metal and dielectric: The metamaterial with metal
filling ratio larger/smaller than one-half is named as the “generalized
metal/dielectric.” Interestingly, the surface plasmon polariton (SPP) at a
metal/dielectric interface can be understood as the limiting case of a
topological edge state.
Funder
Imperial
College London
Gordon
and Betty Moore Foundation
Horizon
2020 Action Project
Engineering and Physical Sciences Research 232
Council
UK STFC
Ernest Ruther-Ford Fellowship
Publisher
Proceedings of the National Academy of Sciences
Reference29 articles.
1. C. Kittel , Introduction to Solid State Physics
(Wiley, New York, NY, ed. 8, 2005).
2. J. D. Jackson , Classical Electrodynamics (John Wiley
& Sons, 2012).
3. N. W. Ashcroft , N. D. Mermin , Solid State Physics
(Brooks Cole, Belmont, CA, 1976).
4. S. A. Maier , Plasmonics: Fundamentals and
Applications (Springer Science & Business Media,
2007).
5. Metamaterials and Negative Refractive Index
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