Comments on 'Waves in planar waveguide containing chiral nihility metamaterial'

摘要

In electromagnetics, Lakhtakia [1] introduced the concept of nihility medium. Later, Tretyakov et al. [2] extended the concept of nihility for the isotropic chiral medium. Various papers on chiral nihility medium are contributed by different authors, but the contribution by Cheng et al. [3] is the most interesting and stimulating. Unfortunately, there are some typographical errors which cause serious difficulties in the understanding of the work and confusions about the conclusions drawn. The paper [3] published in Optics Communications concludes that "total electric field in chiral nihility medium disappears when a perfect electric conducting (PEC) interface placed in chiral nihility medium is excited by a plane wave or a spectrum of plane waves". In the present communication, typographical errors in the paper [3] are mentioned and their error free form is given. Typo errors in polarization vectors lead to existence of both electric and magnetic fields in chiral nihility region backed by PEC. In order to find an error free form of polarization vectors, reflection of electromagnetic plane wave from a PEC interface placed in an isotropic chiral medium has been considered. Imposing the nihility condition, results corresponding to chiral nihility medium are derived. It is concluded that negative reflection occurs at the interface of chiral nihility medium and perfect electric conducting plane. Disappearance of total electric field in chiral nihility medium can be verified very easily and typo error in the polarization vectors can be mentioned.