Microwave transmission behavior of the single dissymmetrical hexagonal split-ring resonators

This paper had been comparing the performance of the normal patch antenna with single complimentary SRR patch antenna. Four different shapes of single complimentary split ring resonator structure had been incorporated into the microstrip patch antenna - square, circular, triangular, and rhombic. This simulation works had been done in CST Microwave Studio simulation software. The operating frequency of this antenna is 2.40 GHz for Wireless Local Area Network (WLAN) application. The parameters that considered in these works are return loss, resonant frequency, input impedance, gain, radiation pattern and bandwidth. The focusing parameter is to achieve the best gain performance that obtained from the single complimentary split ring resonator patch antenna. The addition of square SRR onto patch antenna will improve the gain from 6.334 dB to 6.508 dB.

Microplasmas generated by a single split-ring resonator and a dual concentric split-ring resonator operating at the same frequency are compared. Argon is used as the working gas and held at a pressure of 0.5 Torr. The surface electric fields in the resonators were simulated to gain insight into the behavior of the fields in each device. Double Langmuir probes were used to measure the plasma density and electron temperature in a 2D plane 2 mm above the surface of the resonators. The single and the concentric ring resonators both had a maximum electron temperature in the discharge gap of 2.5 eV. The single and concentric split-ring resonators had the same maximum measured plasma density of 1.19 × 1017 m−3. Plots of the measured properties and comparisons with electric field simulations show the field coupling to the concentric ring and ignition produced in the secondary discharge gap. The concentric ring resonator has more spatially uniform temperature and density distributions relative to the single split-ring resonator.

Metamaterial-based sensor design using split ring resonator and Hilbert fractal for biomedical application

Electromagnetic metamaterials (MMs) consisting of highly conducting sub-wavelength metallic resonators enable many unusual electromagnetic properties at user defined frequencies which are not permissible with the naturally occurring materials [1, 2]. Generally the electromagnetic properties of metamaterials are controlled by the design variation of the MM unit cell, often termed as meta-molecule, consisting of single or multiple metallic split ring resonators (SRRs). These metallic resonators are quite often termed as meta-atoms too. The near field electromagnetic coupling between these meta-atoms exhibits an important role in modulating the fundamental resonances of the metamaterials [3-5].

A novel composite right-/left-handed transmission line (CRLH TL) and its equivalent circuit model are proposed based on cascaded complementary single split ring resonator (CCSSRR). It features an intrinsically balanced wider band and an additional transmission zero above the right-handed band relative to CRLH TL using complementary single split ring resonator and complementary split ring resonators. Moreover, two single negative (SN) metamaterial (MTM) TLs constructed by using complementary electric inductive-capacitive resonator on the conductor strip and on the ground, respectively, are researched. Both SN MTM TLs exhibit electric resonance above the fundamental magnetic resonance. For application, a monoband (MB) bandpass filter (BPF) covered WLAN band, and a dual-band (DB) BPF covered satellite DMB band and WiMAX band are designed, fabricated, and measured. The SN MTM TLs are adopted for the sake of deep and wide out-of-band suppression while CRLH MTM TLs using square-shaped and Sierpinski-shaped CCSSRR are critical factors of the MB and DB behavior. © 2011 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2012. © 2012 Wiley Periodicals, Inc.

Split-ring resonators (SRRs) are one of the most common building blocks to design metamaterials operating over a large range of frequencies in the electromagnetic spectrum. Here we acquire s-SNOM images with high signal-to-noise ratio on SRRs by scattering-type scanning near-field optical microscopy (s-SNOM) in the terahertz (THz) domain. By mapping the electric field distribution with subwavelength spatial resolution, we observe clear spatial asymmetries within a single SRR. These effects are more pronounced for the SRRs designed to resonate at the frequency of the probing laser (2.52 THz), compared to the SRRs that do not support a resonant mode at this frequency. This asymmetrical distribution is attributed to combined far-field and near-field multiplication effects, which depend on the position of the probing tip on the micro-resonator.

we report our investigation on third harmonic generation (THG) in the terahertz (THz) regime using double resonant frequency selective metasurface composed of square-shaped periodic complementary single split ring resonators.

It was shown theoretically and experimentally that a metamaterial composed of periodically positioned split ring resonators (SRR) can lead to a negative effective permeability μeff close to its resonance frequency. In this paper, the nearest neighbor interactions between hexagon SRR were investigated in experiment. The experimental results show that there is only one resonance frequency for a one-dimensional negative permeability μeff material. The main and defect resonance frequencies have a shift when the defect SRR is introduced into the materials, and the shifts of which increase with the resonance frequency difference between defect and based SRR. It is thought that the interaction between SRR becomes stronger when the resonance frequency of the defect SRR is close to that of the based SRR.

We propose a mirrored arrangement of asymmetric single split ring resonators (ASRs) that dramatically enhances the quality factor of the inductive-capacitive resonance. In a regular non-mirrored arrangement, the surface current modes are all oriented in phase. Hence, light scattered by individual ASRs interferes constructively. In contrast, the proposed configuration sustains surface currents that are oppositely oriented for neighboring ASRs, in turn leading to the cancellation of the net dipole moment accompanied by destructive interference of the scattered fields. The proposed arrangement holds promise to suppress radiation losses in terahertz, microwave and infrared plasmonic metamaterials.

An ultra-wideband three-layer 90° polarization rotator based on double split-ring resonators is proposed in this paper. The structure is constructed from three layers separated by two air gaps. The top and bottom layers are wire grid orthogonal to each other, while the middle layer consists of double split-ring resonators. The purposed polarization rotator is able to rotate the incident linearly polarized plane wave in the frequency band from 3.70 to 14.76 GHz with a minimum of 90% cross-polarization transmission. Compared to previous works based on single split-ring resonator, our improved design exhibits a fractional bandwidth of 119.8%, which is wider than the reported design by 27.2%.

In this paper, a novel tri-band bandstop filter (BSF) based on hexagonal split ring resonators (H-SRRs) is presented. The proposed filter consists of a microstrip fed line loaded with three H-SRRS. Various modifications to the HSRR are made and their effects on the permittivity are discussed. The filter is fabricated and measured. Good agreement is obtained between numerical and experimental results.

We present the design, fabrication, and characterization of a band pass filter with a center frequency of 28 GHz using a Half Mode Substrate Integrated Waveguide (HMSIW) architecture on a smooth and thin fused silica substrate for the reduction of insertion loss. Filter properties are implemented by using a single complimentary split ring resonator (CSRR) structure. High out-of-band attenuation is achieved by using four spur line structures embedded in the microstrip feed line, which contributes to overall size reduction of the device. Design is simulated using high frequency structural simulator (HFSS). Devices are fabricated using laser machining and microfabrication. The measured insertion loss is 3dB and the total area of the device is 5.719 mm^2.

High-order harmonic generation (HHG) in solids—the frequency up-conversion of an optical signal—is governed by symmetries. At terahertz (THz) frequencies, HHG is a key technology to access high-frequency spectral windows that are usually difficult to cover using conventional solid-state laser technologies. This effect has been recently exploited in graphene, where HHG has been demonstrated, albeit only at odd multiples of the driving frequency owing to its inherent centro-symmetry. In topological insulators (TIs), the combination of spin–orbit interaction and time-reversal symmetry create an insulating bulk state with an inverted band order, inseparably connected with conducting surface states. TIs have been predicted to support unconventional high harmonic generation from the bulk and topological surface, which are usually difficult to distinguish. However, no experimental results have been reported, so far. Here, we exploit the strong optical field amplification provided by an array of single or double split ring resonators, with embedded Bi2Se3 or (InxBi(1−x))2Se3/Bi2Se3 Van der Waals heterostructures, to achieve up-conversion in the 6.4 (even)–9.7 (odd) THz frequency range. This results from bulk centro-symmetry (odd states) and symmetry breaking in the topological surface states (odd and even).

In this paper, we propose a microfluidic dual-band bandpass filter with frequency switching capability. The proposed filter is composed of two split ring resonators (SRRs) and a microfluidic channel. The lower resonant frequency is determined by only the length of the SRRs, whereas the higher resonant frequency is determined by the lengths of the SRRs and the stub. We use this characteristic to fix the lower resonant frequency by fixing the SRR length, and we tune the higher resonant frequency by controlling the stub length using a microfluidic channel. We confirmed that this filter has two states, through EM simulation and measurements.

In this article, a metasurface (MS) is placed as superstrate to counteract the effect of mutual coupling in linear antenna array in X-band. The metasurface is single layered and consist of single split ring resonator (SRR) and two I-shaped structures. The proposed metasurface can curb the interactions between adjacent antenna elements by collimating the electric field and reduce horizontal magnetic field interactions due to its negative refractive index and mu-near-zero property. The functioning of metasurface is tested by placing it above a 1×3 patch antenna. The experimental measurement shows an isolation below -25 dB in the 5.12% operational bandwidth with maximum isolation of -38.2 dB for an edge-to-edge distance of only 0.16λo. The active radiation pattern indicates an improved cross-polarization levels to below -30 dB, in both the orthogonal planes. The performance of MS is further tested for a 1×7 linear array where a 9.2 dB reduction in coupling value is observed. On placing the MS on the array there is no change in the operational bandwidth indicating that no modifications is needed in the antenna array geometry making it a preferable and easily transferrable solution to already existing antenna array.