Does Chaotic Scattering Affect The Extinction Efficiency In Quasi-Spherical Scatterers?

Infrared spectra of cells and tissues exhibit a variety of scattering phenomena that have been studied in the literature during recent years. The most intriguing scattering phenomena that have been observed are so-called Mie-type scattering phenomena. Mie-type scattering occurs in nearly spherical-shaped scatterers, when the size of the scatterer is of the same order as the wavelength employed. Mie scattering is the scattering of electromagnetic radiation at a spherical scatterer and was solved analytically by Gustav Mie already in 1908. The analytical Mie solutions have been used in model-based pre-processing approaches for retrieving pure absorbance spectra from highly distorted, measured infrared spectra of cells and tissues. While existing iterative algorithms have been shown to be able to retrieve pure absorbance spectra efficiently in many practical situations, the question remains to what extent the analytical Mie solutions describe the extinction efficiency in practical situations, where the shape of cells deviate considerably from perfect spheres.From other fields it is well known that deviations of shapes can change the absorption properties of a scatterer considerably. In the context of chaos in wave systems, it was shown that chaotic scattering may enhance absorption properties of a scatterer considerably. Small deviations from perfect spherical scatterers that involve changes in the size of the refractive index, may easily lead to a transition between regular and chaotic scattering. The aim of the current study is to investigate how deviations from a spherical scatterer leading to chaotic scattering can change the extinction properties of the scatterer. For this purpose, we investigate a scatterer that is shaped like a Bunimovich billiard. A Bunimovich-billiard shaped scatterer has been shown to be chaotic, and it allows to study the gradual transition between a chaotic scatterer (billiard) and a regular scatterer (sphere).