Diffraction of quasi-nondiffracting Bessel beam by an impedance disc in an anisotropic plasma.

Abstract

The diffraction of the so-called nondiffracting Bessel beam by an impedance disc immersed in an anisotropic medium is examined. The external uniform magnetic field, which makes the plasma anisotropic, is taken to be rotational as opposed to being parallel to the edge of the problem geometries in the literature. Thus, the appropriate dielectric matrix that models the anisotropic region under the rotational dc external magnetic field is derived for the first time, to the best of our knowledge. Upon considering the geometric optics waves, the total scattered waves are obtained with the diffracted waves by using the definition of high-frequency asymptotic expressions associated with the scattered waves at the transition regions. The results are expressed in terms of the Fresnel functions so that the wave behaviors in the transition regions are uniform. The solutions are compared numerically with existing studies in the literature, including limit values.