| Autor: |
Alessandro Salandrino, Shima Fardad, Eric L. Schweisberger |
| Rok vydání: |
2020 |
| Předmět: |
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| Zdroj: |
Metamaterials, Metadevices, and Metasystems 2020. |
| DOI: |
10.1117/12.2568035 |
| Popis: |
We discuss a new class of nonlinear absorbers termed Plasmonic Parametric Absorbers (PPA) relying on the recently introduced concept of Plasmonic Parametric Resonance (PPR). In contrast with conventional localized plasmonic resonances, whereby modes are excited directly by an external field of frequency and spatial profile matching those of a given mode of the plasmonic particle, PPR is a form of amplification in which a pump field transfers energy to a mode in an indirect fashion. In PPR in fact the modes of a plasmonic structure are amplified by means of a temporal permittivity modulation of the background medium interacting with an appropriate pump field. Such permittivity variation translates into a modulation of the modal resonant frequency, and under specific conditions amplification can occur. Among the unique characteristics of PPR is the possibility of accessing modes of arbitrarily high order with a simple spatially uniform pump, provided that such pump exceeds a certain intensity threshold. It is such threshold behavior that can lead to PPAs, a type of nonlinear metamaterial absorber with rather unique properties. PPAs exhibit a reverse saturable absorption behavior whereby an incident field that is parametrically resonant with one or more of the modes of a plasmonic particle experiences a strongly enhanced absorption whenever its intensity exceeds the relevant PPR threshold. Such effect makes PPAs very promising candidates for optical limiting applications, in addition of being of fundamental interest in the emerging field of nonlinear plasmonics. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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