Perfect Metamaterial absorber based energy harvesting application in ISM Band

An electromagnetic (EM) energy harvesting application based on metamaterial absorber (MA) is introduced and discussed in this paper. This application is operating at ISM band (2.40 GHz) which is especially chosen due to its wide usage area. Square ring resonator (SRR) which has two gaps and resistors across the gaps on it is used. Chips resistors are used to deliver power to any active component. Transmission and reflection characteristics of metamaterial absorber (MA) for energy harvesting application are investigated. 83.6% efficient for energy harvesting application is realized in this study

Perfect Metamaterial absorber based energy harvesting application in ISM Band

An electromagnetic (EM) energy harvesting application based on metamaterial absorber (MA) is introduced and discussed in this paper. This application is operating at ISM band (2.40 GHz) which is especially chosen due to its wide usage area. Square ring resonator (SRR) which has two gaps and resistors across the gaps on it is used. Chips resistors are used to deliver power to any active component. Transmission and reflection characteristics of metamaterial absorber (MA) for energy harvesting application are investigated. 83.6% efficient for energy harvesting application is realized in this study

Some aspects of mass-energy equivalence which appears in left-handed metamaterials

In this work, the concept of mass-energy equivalence in left-handed metamaterials is discussed by following Einstein's box thought experiment. Left-handed metamaterials are artificial composite structures that exhibit unusual properties, especially negative refractive index, in which phase and group velocities are directed oppositely. Equation E = mc2 assumes that, in vacuum, the propagation of an electromagnetic radiation from emitter to receiver is accompanied by the transfer of mass. It was hypothesized previously that if the space between emitter and receiver is medium with a negative refractive index, then radiation transfers the mass not from the emitter to receiver as expected, but rather from the receiver to the emitter due to the opposite directions of phase and group velocities. In this paper, it is shown that even though one radiating atom is taken, the negative mass transferring must be in force. In particular, it means that, if the atom radiates a photon in a medium with negative refractive index, photon transfers the mass not from the atom, but to the atom

Realization of polarization-angle-independent fishnet-based waveguide metamaterial comprised of octagon shaped resonators with sensor and absorber applications

A new fishnet-based waveguide metamaterial structure for the microwave region is introduced and investigated both numerically and experimentally. The proposed model is designed and fabricated on both sides of the substrate and exhibits strong metamaterial behavior (such as negative material parameters: i.e. negative permittivity, negative permeability, and negative index of refraction) at the resonance. Only one single slab is used in the simulation and experiment which provides a reduction in the number of the required samples with respect to its free-space and/or waveguide counterparts. This means that a small-sized metamaterial structure is simulated, measured, and characterized by placing the sample in the waveguide. The effective medium theory is employed for the characterization of the structure and the left-handed region is identified. The measured results are in good agreement with the simulated ones which show that the proposed structure operates well in terms of metamaterial behavior and can be used in waveguide miniaturization and waveguide-based applications such as antennas, filters, sensors, absorbers, imaging systems, and so on. To validate this claim, sensor and absorber applications are selected and the simulation results show that the proposed sensor and absorbers devices operate well under the defined conditions

Metamaterial Absorber Based Multifunctional Sensors

In this paper, several important applications of a metamaterial absorber (MA) based sensors such as temperature, pressure, moisture, and density are presented. Since the sensing ability mostly considers the resonance frequency, the frequency range where the resonance shifts occur linearly or non-linearly depending on the temperature, pressure, moisture, and density changes is selected carefully. The model is composed of X shaped resonators (XSR), dielectric substrate, the sensing layer, dielectric substrate again, and metallic plate, in order. Sensing layer changes its dielectric behavior depending on the temperature, pressure, moisture, and density variations and letting us to determine the unknown values of the mentioned parameters. According to the results, the proposed model can be used in myriad sensing applications for the studied microwave frequency band. (C) 2016 The Electrochemical Society. All rights reserved

Perfect metamaterial absorbers with polarization angle independency in X-band waveguide

The design and characterization of perfect metamaterial absorbers (MAs) based on simple configurations including square- and triangle-shapes, which operate in X-band frequency region are numerically and experimentally investigated. The proposed MAs provide perfect absorption with the polarization angle independency. In X-band wave guide, the absorption rates are 99.69% and 99.97% at the resonance frequencies of 10.57 GHz and 10.93 GHz for the square- and triangle-shaped MAs, respectively. In addition, the same configurations are numerically tested under free space boundary conditions to compare and discuss the obtained results. The suggested MAs enable myriad potential application areas for security and stealth technologies in X-band including wireless communication

Tunable Graphene Integrated Perfect Metamaterial Absorber for Energy Harvesting and Visible Light Communication

Tunable graphene integrated metamaterial absorber is proposed for energy harvesting and visible light communication. The structure provides unity absorption in the visible spectrum in which it can be used perfect absorber for energy harvesting. In addition, it also provides tunability because of the graphene conductivity to be used as photoconductive or thermal switch for visible light communication

Characterization of Metamaterials using a New Design and Measurement Technique for Microstrip Circuit Applications

Characterization of a metamaterial based on an S-Shaped resonator and a feeding transmission line using a new measurement technique is studied in this paper. First, the metamaterial is designed and simulated using conventional methods. Then, it is fabricated on microstrip and excited by using a microstrip transmission feedline. Measurements were carried out using a vector network analyzer by (SubMiniature version A) SMA coaxial terminations without needing any waveguide transmission lines. For both simulated and measured results, the effective constitutive parameters are retrieved and analyzed. Results show the practicality and feasibility of the proposed measurement method in the characterization of metamaterials for microstrip based microwave circuit applications

A Frequency Tunable Metamaterial Resonator using Varactor Diodes

A frequency tunable resonator topology is proposed that consists of an S-shaped resonator, a ground frame and a feeding transmission line. Tunability is achieved by using reverse biased varactor diodes employed at critical locations on the structure. As well as being a tunable resonator, the structure also provides tunable metamaterial properties. Reflection and transmission parameters, electric and magnetic field distributions, and permittivity and permeability at each tuned frequency were analyzed and shown. Simulation and measured results agree well and demonstrate about 28% frequency tunability

Polarization angle insensitive dual-band perfect metamaterial absorber for solar cell applications

A metamaterial absorber that effectively harvests solar energy is being proposed in this paper using a simple and high flexible structure. The proposed structure unit cell comprises of three vital layers. The ground metallic plane, an intermediate dielectric spacer while patches are wisely prepared on the top of a dielectric spacer. Geometrical parameters of the proposed metamaterial is studied in order to get insight on their impact for the absorption behaviour of the structure. The results from simulation provides two excellent absorption resonance (99.96% and 99.37%) in the visible spectrum range of electromagnetic wave. Due to the excellent symmetry of the proposed metamaterial design, its absorption coefficient is polarisation insensitive for a wide range of incident angles of electromagnetic radiations. (C) 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinhei