MERCREDI 14 OCTOBRE 2009
14 heures
Salle Séminaire 5
Centre de Physique Théorique
Marseille-Luminy

Guy Bouchitté
USTV Toulon

Titre: Approches multi-échelles des effets de résonance
dans les cristaux photoniques

Abstract: It is now commonly admitted that obstacles made of metallic
or dielectric inclusions placed periodically in a suitable way can
behave like homogeneous materials with negative refractive index (or
other rather unexpected exotic properties). We will present several 3D
situations where such behaviors can be recovered rigorously by using
multi-scale methods:

- High conductivity fibers with very small filling ratio (negative
effective permittivity)

- Pendry metallic split ring structures

- High contrast dielectric inclusions (artificial magnetism and
negative permittivity)

In all these cases, the key point relies on a spectral problem in the
periodic cell which accounts internal resonances and allows to decribe
small scale oscillations of the electromanetic field. Due to the
extreme values of the permittivity in the inclusions, these
micro-resonances are compartible with a possibly large incident
wavelength.

The macroscopic behavior of the photonic crystal is then identified by
using classical homogenization techniques.