ANALYTICAL ANTENNA MODEL FOR CHIRAL SCATTERERS - COMPARISON WITH NUMERICAL AND EXPERIMENTAL-DATA

An analytical model for polarizability dyadics of small chiral conduct ive particles in free space or those embedded in a lossy material is p resented and discussed. Chiral particles are modeled by a wire loop co nnected to two straight wire elements. The electromagnetic analysis is based on the replacement the particles by two connected antennas repr esenting the wire and loop portions. Analytical expressions for polari zabilities are given, For electrically small particles, a lumped-eleme nt equivalent circuit can be constructed and the polarizabilities can be expressed in terms of equivalent circuit parameters, It Is shown th at the wire-and-loop antenna model for scatterers satisfies the recipr ocity condition and other basic physical requirements, Approximate ana lytical expressions are compared with numerical simulations and with t he experimental data on reflection from single chiral particles, and t he results are seen to be in good agreement. The model can be used in analytical modeling of chiral and omega composite materials.