|Title:||Branch Cuts and Resonances for Metamaterials and Plasmonics|
|Speaker:||McPhedran, Ross C.|
|Group/Series/Folder:||Record Group 8.15 - Institute for Advanced Study|
Series 3 - Audio-visual Materials
|Notes:||Croucher Advanced Study Institute on New Materials and New Concepts for Controlling Light and Waves. Talk no.20|
Host: HKUST Institute for Advanced Study.
Sponsor: The Croucher Foundation.
Abstract: Resonances in physics correspond to poles of a response function, and are of interest because they give rise to large responses to an input signal, and rapid changes in output as a parameter such as frequency is varied. There are however circumstances under which a system response function can exhibit branch cut characteristics rather than isolated resonances. This may be of interest in applications where heightened response is desired over a continuous band of frequencies, rather than at well-separated values.
The talk will discuss situations which give rise to poles in the response function, using the example of localized plasmons and formulae of the Maxwell-Garnett type. The talk will also discuss effective media formulae, which typically give rise to formulae involving branch cuts of the square root function. The talk will contrast these with the behaviour of solutions associated with inclusions of negative permeability or permittivity, and having sharp corners. These have branch cuts which depend on the corner angle, and may provide a type of strong broadband resonance useful in applications of plasmonics, and in new designs for metamaterials.
Duration: 37 min.
|Appears in Series:||8.15:3 - Audio-visual Materials|
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