Abstract
An analytical solution is developed for spherical wave scattering by a slit in an infinitely perfectly conducting sheet in a homogeneous biisotropic medium. Interestingly, the vector diffraction problem is reduced to the scattering of a single scalar field, this scalar field being the normal component of either a left-handed or a right-handed Beltrami field. The point source is assumed to be far from the slit so that the incident spherical wave is locally plane. The slit is wide and the sheet thin, both with respect to wavelength. By using the Fourier transform technique the boundary-value problem is transformed into Wiener-Hopf equation that is solved approximately. The diffracted wave field is studied in the far field of the slit. The diffracted field is the sum of the wave fields produced by the two edges of the slit and an interaction wave field. [PUBLICATION ABSTRACT]