Affiliated with the
Communication & Space
Sciences Laboratory

Novel Electromagnetic Metamaterials

FDTD Modeling of Bi-anisotropic and Double-Negative Media

..: Movies :..


Index of Refraction of Zero: Cylindrical monochromatic source in front of slab (1.22 λ by 12.24 λ slab at 3.67 THz)

 


Index of Refraction of Zero: Cylindrical monochromatic source inside of slab ( 1.22 λ by 12.24 λ slab at 3.67 THz )

 


Index of Refraction of Negative One
( 1.15 λ by 11.54 λ slab at 3.46 THz )

 


Index of Refraction of Negative One
( 2.3 λ by 11.54 λ slab at 3.46 THz )

 

BI-FDTD Simulation of Electromagnetic Wave Interaction with Non-dispersive Chiral Metamaterial Half-Space

Ex Field Component

           Yellow :  E
           Blue:      E+
           Red:      E-

Ey Field Component

BI-FDTD Simulation of Electromagnetic Wave Interaction with Dispersive Chiral Metamaterial Slab

            Blue:      E
            Black:   E+
            Red:      E-

Modeling of Electromagnetic Wave Interactions With Bi-isotropic and Bi-anisotropic Meta-materials Using A New Wavefield Decomposition Finite Difference Time Domain (WD-FDTD) Technique Go/
by A. Akyurtlu and D. H. Werner



..: References :..

1-) BI-FDTD: A Novel Finite-Difference Time-Domain Formulation for Modeling Wave Propagation in Bi-Isotropic Media
by A. Akyurtlu and D. H. Werner

ABSTRACT: This paper presents a newly developed FDTD technique, referred to as BI-FDTD, for modeling electromagnetic wave interactions with bi-isotropic (BI) media. The theoretical foundation for the BI-FDTD method will be developed based on a wavefield decomposition. The main advantage of this approach is that the two sets of wavefields are uncoupled and can be viewed as propagating in an equivalent isotropic medium, which makes it possible to readily apply conventional FDTD analysis techniques. The BI-FDTD scheme will also be extended to include the dispersive nature of chiral media, an important subclass of bi-isotropic media. This extension represents the first of its kind in the FDTD community. Validations of this new model are demonstrated for a chiral half-space and a chiral slab.




2-) A Novel Dispersive FDTD Formulation for Modeling Transient Propagation in Chiral Metamaterials
by A. Akyurtlu and D. H. Werner

ABSTRACT: Chiral media engineered for applications at microwave frequencies can be described as metamaterials composed of randomly oriented helices (with sizes typically less than a wavelength) embedded within an achiral background that is characterized by its permittivity and permeability. Chiral metamaterials embody properties of magneto-electric coupling and polarization rotation. Chiral media are also highly dispersive and no effective full-wave time domain formulation has been available to simulate transient propagation through such an important class of metamaterials. A new Finite-Difference Time-Domain (FDTD) technique is introduced in this paper to model the interaction of an electromagnetic wave with isotropic dispersive chiral metamaterials, based on the implementation of a wavefield decomposition technique in conjunction with the piecewise-linear recursive convolution method. This formulation represents the first of its kind in the FDTD community. The FDTD model is validated by considering a one-dimensional example and comparing the simulations with available analytical results. Moreover, the FDTD technique is also used to investigate the propagation of electromagnetic waves through multilayered metamaterial slabs that include dispersive chiral and double-negative media. Hence, this model enables the investigation of complex dispersive metamaterials with magnetoelectric coupling and double-negative behavior as well as facilitates the exploitation of their unique properties for a variety of possible applications.




3-) Modeling of Transverse Propagation Through a Uniaxial Bi-anisotropic Medium Using the Finite-Difference Time-Domain Technique
by A. Akyurtlu and D. H. Werner
2002 IEEE Antennas and Propagation Society International Symposium
San Antonio, Texas, June 16-21, 2002




4-) Novel FDTD Approach for the Analysis of Chiral Cylinders
by Andrey Semichaevsky, Alkim Akyurtlu, Douglas Kern, and Douglas H. Werner
2004 IEEE International Symposium on Antennas and Propagation, Monterey, California, June 20-26

ABSTRACT: This article deals with the analysis of electromagnetic wave scattering by a chiral cylinder in free space. Techniques for the numerical electromagnetic analysis of biisotropic media based on the finite difference time domain method have been previously proposed and investigated. One of these techniques, called BI-FDTD, is used in this paper to compute the scattered field. The distinctive feature of the technique is the use of two independent sets of wavefields representing the left- and right-polarized waves in the chiral medium. The simulation results are compared with the analytical solutions for the circular cylinder derived using the plane wave decomposition into spherical harmonics.




5-) Modeling of Transverse Propagation Through a Uniaxial Bi-anisotropic Medium Using the Finite-Difference Time-Domain Technique
by A. Akyurtlu and D. H. Werner
IEEE Transactions on Antennas and Propagation, Vol. 52, No. 12, pp. 3273-3279, Dec. 2004.

ABSTRACT: This paper presents an extension of the recently developed finite-difference time-domain (FDTD) technique for modeling electromagnetic wave interactions with bianisotropic (BI) media, known as BI-FDTD, to include the more general class of bianisotropic materials. This new FDTD formulation is called BA-FDTD. The theoretical foundation for this method is based on a wavefield decomposition technique. The formulations based on the application of this wavefield decomposition technique to BA media will be presented. Validations of this new model are demonstrated for the interaction of an electromagnetic wave propagating transversely through a uniaxial BA half-space.




6-) Novel BI-FDTD Approach for the Analysis of Chiral Cylinders and Spheres
by Andrey Semichaevsky, Alkim Akyurtlu, Douglas Kern, Douglas H. Werner, and Matthew G. Bray.
IEEE Transactions on Antennas and Propagation, vol. 54, No. 3, pp. 925-932, March 2006.

ABSTRACT: A versatile time-domain technique, known as bi-isotropic finite difference time domain (BI-FDTD), has recently been introduced for the numerical analysis of electromagnetic wave interactions with complex bi-isotropic media. However, to date only one-dimensional BI-FDTD schemes have been successfully
implemented. This paper presents novel two-dimensional (2-D) and three-dimensional (3-D) dispersive BI-FDTD formulations for the first time. The update equations for these new 2-D and 3-D BI-FDTD approaches are developed and applied to the analysis of electromagnetic wave scattering by chiral cylinders and spheres in free space. The distinctive feature of this technique is the use of two independent sets of wavefields representing the left- and right-polarized waves in the chiral medium. This wave-field decomposition approach allows dispersive models for the chirality parameter as well as the permittivity and permeability of the medium to be readily incorporated into an FDTD scheme. The 2-D and 3-D BI-FDTD simulation results are compared with available analytical solutions for the scattering from a circular chiral cylinder and a chiral sphere respectively.




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