Pierre Godard, Frédéric Zolla and André Nicolet
The purpose of this paper is to discuss two‐dimensional electromagnetic diffraction by a finite set of parallel nonlinear rods (optical Kerr effect). To point out the versatility…
Abstract
Purpose
The purpose of this paper is to discuss two‐dimensional electromagnetic diffraction by a finite set of parallel nonlinear rods (optical Kerr effect). To point out the versatility of this approach, a nonlinear (Kerr‐effect) finite crystal is considered.
Design/methodology/approach
In this paper, a new route for obtaining the scattered field by nonlinear obstacles is proposed. The basic idea consists in simulating the real incident field (e.g. plane waves) by a virtual field emitted by an appropriate antenna, located in a meshed domain, and encompassing or lying above the obstacles. This latest problem is then solved by a finite element method that is well suited to take into account the material inhomogeneities due to the nonlinearity of the permittivity.
Findings
The transmission through a finite Kerr crystal doped by a microcavity is given and a resonant wavelength is obtained. At this resonant wavelength, it is shown that the nonlinearity has a large influence on the behaviour of the electromagnetic wave.
Originality/value
Introducing the concept of virtual antenna, the paper proposes a rigorous treatment of the scattering of an electromagnetic wave by a bounded nonlinear obstacle of arbitrary shape.
Details
Keywords
André Nicolet and Frédéric Zolla
Proposes to posit a clear definition of the energy stored in general electromagnetic media.
Abstract
Purpose
Proposes to posit a clear definition of the energy stored in general electromagnetic media.
Design/methodology/approach
A general setting of thermodynamics using differential geometry is used and it is shown how the Poynting identity fits in.
Findings
A general method of defining the energy storage and dissipation in a general media is stated.
Research limitations/implications
It appears that the definition of the energy stored in a dispersive media is not a state variable and depends on the history of the field variation.
Practical implications
If an electromagnetic model has to be coupled to a mechanical or thermal one, the associated forces and/or heat dissipations may not be clearly defined if one merely knows the electromagnetic constitutive relations.
Originality/value
It proposes a very general setting for the thermodynamic of electrodynamic media.
Details
Keywords
Y. Ould Agha, F. Zolla, A. Nicolet and S. Guenneau
The purpose of this paper is to present a complete analysis of leaky modes within a microstructured optical fibre (MOF). Some new numerical results illustrating the versatility…
Abstract
Purpose
The purpose of this paper is to present a complete analysis of leaky modes within a microstructured optical fibre (MOF). Some new numerical results illustrating the versatility and accuracy of our approach are to be given.
Design/methodology/approach
A method involving both finite elements and perfectly matched layer (PML) is proposed.
Findings
A rigorous definition of the leaky modes is proposed that leads to a proof of the validity of the PML approach together with a rule for the choice of the PML parameters.
Originality/value
The choice of parameters associated with the PML are discussed in great detail. The accuracy of the constant of propagation (and especially the imaginary part) are highlighted.
Details
Keywords
S. Guenneau, S. Lasquellec, A. Nicolet and F. Zolla
In this paper, we study a new class of optical fibers to be utilized in future optics and optoelectronics. These so‐called photonic band gap (PBG) waveguides can be classified…
Abstract
In this paper, we study a new class of optical fibers to be utilized in future optics and optoelectronics. These so‐called photonic band gap (PBG) waveguides can be classified into a fundamentally different way to all optical waveguides and possess radically different guiding properties due to PBG guidance, as opposed to guidance by total internal reflection.