Evaluation of the E-polarization focusing ability in Thz range for microsize cylindrical parabolic reflector made of thin dielectric layer sandwiched between graphene

Oguzer T. A., ALTINTAŞ A.

IET MICROWAVES ANTENNAS & PROPAGATION, cilt.15, sa.10, ss.1240-1248, 2021 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 15 Sayı: 10
  • Basım Tarihi: 2021
  • Doi Numarası: 10.1049/mia2.12161
  • Dergi Adı: IET MICROWAVES ANTENNAS & PROPAGATION
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, PASCAL, Aerospace Database, Applied Science & Technology Source, Business Source Elite, Business Source Premier, Communication Abstracts, Compendex, Computer & Applied Sciences, INSPEC, Metadex, Civil Engineering Abstracts
  • Sayfa Sayıları: ss.1240-1248
  • Dokuz Eylül Üniversitesi Adresli: Evet

Özet

We consider two-dimensional (2-D) thin dielectric parabolic reflector, covered with graphene from both sides, illuminated symmetrically by an E-polarized electromagnetic plane wave. Our aim is to estimate the focussing ability of such a composite reflector depending on the graphene parameters. We use a version of the two-side generalized boundary condition, modified for a thin multilayer case. The scattering is formulated as an electromagnetic boundary-value problem; it is cast to a set of two coupled singular integral equations that are further subjected to analytical regularisation based on the known Riemann-Hilbert problem solution. Thanks to this procedure, the numerical results are computed from a Fredholm second-kind matrix equation that guarantees convergence and provides easily controlled accuracy. In the lower part of the THz range, high values of the focusing ability are observed even for a thin reflector; they are greater than for a purely dielectric reflector and a free standing graphene reflector. On the other hand, a regime of almost full transparency, intrinsic for the dielectric layer, can spoil focusing ability. Novel aspect is that the location in frequency of this effect can be controlled, in wide range, by changing the chemical potential of graphene.