Light scattering resonances in small particles with electric and magnetic properties

Lorenz-Mie resonances produced by small spheres are analyzed as a function of their size and optical properties (epsilon greater than or less than 0, mu greater than or less than 0). New generalized (mu not equal 1) approximate and compact expressions of the first four Lorenz-Mie coefficients (a(1), b(1), a(2), and b(2)) are calculated. With these expressions and for small particles with various values of e and mu, the extinction cross section (Q(ext)) is calculated and analyzed, in particular for resonant conditions. The dependence on particle size of the extinction resonance, together with the resonance shape (FWHM), is also analyzed. In addition to the former analysis, a study of the scattering diagrams for some interesting values of epsilon and mu is also presented. (C) 2008 Optical Society of America.