Helices of optimal shape for nonreflecting covering

In this paper we study helical inclusions of a certain shape (called the “optimal shape”), such that the electric, magnetic, and magneto-electric polarizabilities are equal, and discuss unusual reflection properties of artificial materials based on such inclusions. We study helical particles with optimized design parameters, which can make the realization of media with equal dielectric and magnetic susceptibilities possible. Not canonical helix, which consists of a split loop with two straight-wire sections, but the true helix, which is obtained by bending a wire with a constant pitch angle is investigated. The geometry of the helices makes it possible to create a composite material with equal permittivity and permeability. In such material optimal helices are located in pairs and each pair consists of the right-handed and left-handed helix. Thus compensation of chiral properties of a material as a whole is achieved.