TPDSci Mie theory Resonances and surface waves

Mie theory: Optical resonances and "surface waves"

Numerical studies (for example, Chılek et al 1985, Conwell et al 1984a) and observations (for example, Ashkin and Dziedzic 1981, Ashkin and Dziedzic 1977) of the spatial distribution of the electromagnetic power in the immediate vicinity of the sphere surface at optical resonance conditions indicate a substantial concentration of that power along the sphere surface. Interestingly, Sorensen and Fishchbach (2000) have shown that, in the first approximation, a power-law-like envelope of the Mie angular patterns plotted vs. the dimensionless product qa, where q is the magnitude of the scattering vector and a is the sphere radius, can be explained by assuming that the electromagnetic field is localized within a thin shell at the sphere surface.

Under the resonance conditions, the power density near the sphere surface may be several orders of magnitude greater than that far from the surface (both inside and outside the sphere). Thus, the optical resonances are sometimes referred to as manifestations of surface electromagnetic waves (for example, Lee et al 1998, Ashkin and Dziedzic 1981, Chılek et al 1980, Ashkin and Dziedzic 1977). See Han et al (2001) for a numerical and experimental study of frequency spectra of surface-waves related oscillations in angular patterns of the intensity of light scattered by water droplets, as well as Hovenac and Lock 1992 for a comprehensive discussion of the surface waves in the context of the Debye series formulation of Mie theory.

CITATION:
Jonasz M. 2006. Mie theory: Optical resonances and "surface waves" (www.tpdsci.com/Tpc/MieOptResSfcWv.php). In: Top. Part. Disp. Sci. (www.tpdsci.com).

HISTORY:
Published: 21-Mar-2006
Modified: 30-Jun-2006
Peer-reviewed: 07-Dec-2006

Topics in Particle and Dispersion Science