Characterization of optical systems with the singularity expansion method
Isam Ben Soltane, Nicolas Bonod
1Aix Marseille Univ, CNRS, Centrale Med, Institut Fresnel, Marseille, France
Linear physical systems and their response are characterized in the harmonic domain by meromorphic functions which naturally possess an analytical continuation into the complex frequency plane, where they are expressed in terms of their discrete set of singularities through the rigorously derived Singularity Expansion Method (SEM). We show that the resulting expansion gives an accurate description of the response of different systems, ranging from the components of the S or T-matrices of cavities to the dielectric permittivity of most materials where it encapsulates and generalizes existing models, using small sets of singularities. In addition, this formalism, which applies to any field of physics, can offer a better some insight into the underlying physics of the systems, or an alternative understanding of the phenomena at play in anomalous behaviors in response curves.
Analytical continuation of the response function of a slab in the complex frequency plane.