Scattering of electromagnetic waves by two parallel chiral circular cylinders

The electromagnetic scattering from two parallel chiral circular cylinders is analyzed using a boundary value problem approach. Both cylinders are assumed to be illuminated by either a transverse electric (TE) or transverse magnetic (TM) wave. The separation of variable technique and proper transformation theorems are used to formulate the solution. The incident fields, scattered fields, and transmitted fields are expanded in terms of the cylindrical vector wave functions. Drude-Born-Fedorov (DBF) constitutive relations and Bohren decomposition formula are used to express the electromagnetic fields inside the chiral cylinders. The boundary conditions are imposed in conjunction with the addition theorem of the Hankel function on the boundary surface of each cylinder. The boundary conditions yield a system of linear equations for each type of polarization which can be numerically solved to obtain the unknown expansion coefficients by a proper truncation of the infinite sums into finite sums.; Numerical results are given to show the effects on co- and cross-polarized echo widths for some selected parameters and geometries. The effects on the back and forward scattering co- and cross-polarized echo widths are also given with respect to the separation distance between two cylinders and angle of incidence. From the numerical results, it can be evident that chirality parameter plays an important role controlling the echo width. The validity and accuracy of the results are compared with available published results for special and limiting cases. Several numerical results are also given for the scattering of electromagnetic waves by single chiral cylinder for both the TM and TE cases and validated with existing published results.