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Updated: Oct 20, 2025

High Resolution Phonon-assisted Quasi-resonance Fluorescence Spectroscopy
Published on: June 28, 2016
Effective medium theory for photonic crystals with quadrupole resonances
Abstract:
An effective medium theory is proposed to characterize two-dimensional dielectric photonic crystals (PCs) exhibiting quadrupole resonances. In addition to the effective permittivity and permeability associated with electric and magnetic dipoles, we obtain a local effective parameter to describe the contributions of quadrupole resonances by taking the low frequency limit of multiple-scattering theory. These effective parameters can be used to predict the characteristics of double-Dirac-cone PCs, showing good agreement with the numerical results. Moreover, we show that, after introducing the new effective parameter, the double-Dirac-cone PCs can be regarded as a generalization of the traditional double-zero-index metamaterials.
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