Showing 3 results for Metamaterials
Mr Mohammadreza Forouzeshfard, Prof. Tomas Tyc, Dr. Mahmood Hosseini Farzad,
Volume 8, Issue 2 (7-2014)
Abstract
Based on transformation optics, we propose an illusion device that can make objects look much smaller and different than they actually are. In particular, the device has a capability to hide a large object (like an elephant) into a small one (like a matchbox). Compared to previous proposals for illusion devices, there is no requirement for negative refractive index or for speed of light going to infinity as in Euclidean invisible cloaks. We demonstrate the functionality of the device by full wave simulations.
Dr Vahid Ahmadi, Mr Saeed Pahlavan,
Volume 10, Issue 1 (4-2016)
Abstract
Photonic crystal design procedure for negative refraction has so far been based on trial and error. In this paper, for the first time, a novel and systematic design procedure based on physical and mathematical properties of photonic crystals is proposed to design crystal equi-frequency contours (EFCs) to produce negative refraction. The EFC design is performed by the help of rectangular stair-case (RSC) photonic crystals. The RSC crystal is then converted to more common structures like pillar crystals by matching Fourier coefficients of periodic electric permittivity. Methods to design common crystals which have approximately equal Fourier components to the RSC crystal are also discussed. The proposed procedure can be used to design metamaterials without the difficulties of large trial and error. The devised procedure can also be applied in designing other structures involving photonic crystals.
Marjan Jafari, Fatemeh Moradi,
Volume 12, Issue 2 (12-2018)
Abstract
A bi-isotropic magneto-electric metamaterials is modeled by two independent reservoirs. The reservoirs contain a continuum of three dimensional harmonic oscillators, which describe polarizability and magnetizability of the medium. The paper aimed to investigate the effect of electromagnetic field on bi-isotropic. Starting with a total Lagrangian and using Euler-Lagrange equation, researcher could obtain a quantum Langevin type dissipative equation for electromagnetic field. Generating functional of the system is obtained by the path integral method and based on the perturbative approach. By generating functional, a series expansion in terms of susceptibility function of the bi-isotropic metamaterials is obtained for correlation function or two-point Green’s function. In special case, the close relationship between statistical mechanics and quantum field theory,which was reflected in the path integral methods, could obtain free energy of electromagnetic field for isotropic metamaterial using two-point Green’s function. As an example, the Casimir force of two polarizable metamaterial spheres by Lorentz susceptibilities was studied. Furthermore, Casimir force of two polarizable-magnetizable metamaterials was calculated.
