Abstract
Plasmon resonance, with strong coupling of light to electrons at a metal-dielectric interface, allows light confinement and control at subwavelength scale. It is fundamentally limited by the inherent mobility of the free electrons, leading to the corresponding nonlocality of the electromagnetic response [C. Ciraci et al., Science 337, 1072 (2012); G. Toscano et al., Nat. Commun. 6, 7132 (2015)]. We report that this nonlocality also results in the formation of a hyperbolic layer near the metal-dielectric interface, with a strong anisotropy of its electromagnetic response. While the resulting hyperbolic blockade leads to the suppression of the conventional plasmon resonance, the hyperbolic layer also supports a different class of surface waves, which offer longer propagation distance and stronger field confinement, simultaneously. Furthermore, these hyperplasmons are not limited to the proximity of the plasmon resonance, which extends the operational bandwidth of plasmonic devices.
- Received 23 January 2018
- Revised 1 June 2018
DOI:https://doi.org/10.1103/PhysRevA.99.023827
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