Scattering, absorption, and extinction by thin fibers

For electromagnetic wave incidence on a thin fiber at an angle theta(i) with the fiber axis, induced currents are described by linear combinations of driven and traveling waves exp(+/- ikz cos theta(i)) and exp(+/- imkz), where the complex factor m serves to remove singularities in the normalizing constants of the currents. The fiber may be solid, hollow, or coated, with quite general constitutive parameters. Results are given for scattering, absorption, extinction, and radar cross sections, using energy conservation and reciprocity as consistency checks, and compared with independent computations, including the Born approximation for tenuous conductors and dielectrics. In addition, the far field amplitude of a 50 wavelength conductor is obtained and compared with the well-known long-wire approximation. (c) 2005 Optical Society of America.