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AP-S/URSI 2019, IEEE International Symposium on Antennas and Propagation and USNC-URSI Radio Science Meeting, Atlanta, ETATS-UNIS, 07-/07/2019 - 12/07/2019; High sensitivity in sensors, large group delays forfilters and slow light can be achieved by engineering electromag-netically induced transparency within a narrow electromagneticspectrum. The induced transparency is due to the eliminationof the effect of a medium caused by interaction betweentwo resonant states often referred to as the bright and darkmodes. Induced transparency are often attained by breaking thestructural symmetry of metamaterials as this allows interactionbetween the two modes. In a case of a given excitation, thereis a need to understand the behaviour of the various modesthus making the application of theory of characteristic modesrelevant to this work. This paper presents an approach toobtain electromagnetically induced transparency for a givenexcitation using the theory of characteristic modes. It presentshow electromagnetically induced transparency in a structurecan be systematically engineered by determining which modesare responsible for its occurrence and how to excite thesemodes. In our example, EIT occurred at 36 GHz wherethere was an interaction between the bright and dark modes.This provides an insightful way for designing structures forelectromagnetically induced transparency applications

2019 13th European Conference on Antennas and Propagation (EuCAP), Cracovie, POLOGNE, 31-/03/2019 - 05/04/2019; Metamaterial inspired designs have been explained with the principle of compensation of stored energy between the antenna and the metamaterial. This compensation can be attributed to the coupling between the metamaterial and the antenna. In this paper, we use the theory of characteristic modes in analyzing the coupling between a metamaterial inspired design and its excitation as well as the coupling between the different modes of a metamaterial inspired design. The result obtained validates and gives more insight into the compensation of stored energy explanation for metamaterial inspired design.

IEEE RADIO 2018, Radio and Antenna Days of the Indian Ocean, Flic en Flac, MAURICE, 15-/10/2018 - 18/10/2018; This paper discusses the problem of integrating metamaterial (MTM) structures with antennas. We present a new approach based on the computation of the energies of the surface current modes by means of the theory of characteristic modes (TCM). We also introduce new simple formulation to compute the stored energy using the impedance operation of the method of moment (MoM). This analysis can be done the antenna (driven element) and the inclusion (resonant element).

APS/URSI 2018 IEEE International Symposium on Antennas and Propagation and USNC-URSI Radio Science Meeting, Boston, ETATS-UNIS, 08-/07/2018 - 13/07/2018; Metamaterials are artificial materials tailored to mold the flow of waves. Selecting a metamaterial for practical application is dependent on its effective parameter which classifies it as being electric or magnetic. This paper presents a theory of characteristic modes based quantitative approach for classifying metamaterial unit cell by means of stored energy. The presented results are promising for systematic design approaches for association of metamaterial unit cell to antennas such as in the design of metamaterial-inspired antennas.

Metamaterials are artificial materials tailored to mold the flow of waves. Selecting a metamaterial for practical application is dependent on its effective parameter which classifies it as being electric or magnetic. This paper presents a theory of characteristic modes based quantitative approach for classifying metamaterial unit cell by means of stored energy. The presented results are promising for systematic design approaches for association of metamaterial unit cell to antennas such as in the design of metamaterial-inspired antennas.

EUCAP 2018, 12th European Conference on Antennas and Propagation, Londres, ROYAUME-UNI, 09-/04/2018 - 13/04/2018; Metamaterials have been extensively used for antenna applications due to their capacity of manipulating the propagation of electromagnetic waves. The selection of a metamaterial for a given application is linked to the physical behaviour whether it is electric or magnetic in the frequency band of interest. In this paper, we present a quantitative approach for the classification of metamaterials by means of stored energies. We employ the theory of characteristic mode in the calculation of the net stored energy by a metamaterial structure. Then the modal results are compared to the classical effective medium approach. We show how the stored energy of a metamaterial inclusion can be easily computed using a commercial software and then used to classify the structure behaviour at a specific frequency. The presented numerical results are very promising and this approach is supposed to aid for the analysis and synthesis of metamaterial for future applications.

International audience; Metamaterials are commonly associated to antennas and other microwave devices due to their unique ability to manipulate electromagnetic waves. In general, the approach used to select metamaterials for a given application is based on a classical approach by extracting the scattering parameters to evaluate the material effective properties. In this paper, we address the problem of evaluation and analysis of a specific metamaterial, a chiral helix metamaterial through the use of two modal analysis Expansion Eigenmode Method and the Characteristic Mode Theory. An interaction of the chiral helix with Circular Polarized electromagnetic plane waves is studied. The modal net stored energy of the metamaterial is also calculated. A good agreement is obtained between the net stored energy calculated by the two methods for the chiral metamaterial. The effect of polarisation on the metamaterial is also highlighted by the modal analysis. These modal approaches applied to chiral metamaterials can be of interest for the design of circularly polarised metamaterial antennas.