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In this study, Chiral Metamaterial Sensor (CMS), which is designed by utilizing a Split Ring Resonators (SRR) has been employed to reveal the two different types of sensor applications by experimentally and numerically. These applications include purity demonstration of methanol, ethanol and isopropyl alcohol (IPA) and fuel adulteration applications for petrol. All of the validations have been realized by measuring the complex permittivity values and reflection coefficients by using a vector network analyzer and a sample holder. For simulation, FIT based simulation program is employed. Both numerical and experimental study results are complying with each other. Sample holder which is developed in this study for microfluidic measurements can easily be tuned for other microfluidic sensor applications thanks to its unique design. Having 280MHz bandwidth with −40dB signal level indicates that the proposed structure is highly sensitive and gives a linear output according to purity and adulteration applications. Whereas, there are many metamaterial researches on purity applications in literature, this is the first study that investigates the purity of methanol, ethanol, isopropyl alcohol (IPA) and fuel adulteration of petrol by using a novel chiral metamaterial sensor designed specifically for the proposed applications.

The detection of branded and unbranded chemical materials is essential for the quality control assessment. In this work, a metamaterial inspired sensor is designed and fabricated, which incorporates oval-shaped wing resonators, in order to use to detect branded and unbranded diesels in the X-band frequency region. The simulation studies were carried out by using the Computer Simulation Technology (CST) Microwave studio. A transmission line was introduced into the sensor design and genetic algorithm was used to optimize the proposed structure. Parametric study was investigated by changing the permittivity, permeability of the sensor layer, width of the transmission line, materials of the substrate layer, and width of the resonator. Results showed that different factors can be considered to sense the chemical materials including the shift in resonant frequency and amplitude variation in the reflection or transmission spectrum. It was found that the sensible variation in the transmission value is about −3.2 dB, which is superior to that reported in literature. It was concluded that the sensor is highly sensitive to distinguish the branded diesel from the unbranded one, which makes it viable for detecting fluidics in the chemical industry and medicine.

In this manuscript, a resonator layer is presented for the purpose of reducing the mutual coupling effect between each antenna element of a cross dipole antenna. In design processes, an artificial neural network approach was used for various resonator designs. In the operating frequency band of 2.2–2.7 GHz, 48 different 6 × 6 resonator layers were created and integrated into the cross dipole antenna to reduce transmission and improve isolation between each antenna elements. Moreover, when training an artificial neural network in the Matlab program, 48 different resonator layers were used with the return losses and transmission values of cross dipole antenna elements. After training process, eight unknown resonator designs were tested and accurate results were obtained. Finally, one of the resonator planes, which was obtained from the artificial neural network, was fabricated and experimentally tested, then an accurate result was obtained. This study provides a good solution, especially for improving isolation in multiport antenna systems, using an artificial neural network approach.

A triple band metamaterial absorber in the terahertz range, incorporating a three closed circle ring resonator, was designed and fabricated on flexible polyethylene terephthalate “PET” substrate. The proposed design was investigated theoretically and experimentally. Computer simulation technology “CST” was used to study the designed structure, while lithography technique was used to fabricate the absorber and terahertz time-domain spectroscopy was utilized to measure the reflectivity. Results showed the presence of three intensive peaks at the resonance frequencies of ‘0.43, 0.61, and 0.88 THz’, which correspond to the absorptivity of 98%, 91%, and 98%, respectively. The sensitivity of the three peaks was found to be ‘70.5, 133, and 149.5 GHz/RIU’, respectively. The parametric studies and field distributions were analysed. Furthermore, the proposed design exhibited polarization insensitivity for both transverse electric “TE” and transverse magnetic “TM” modes from 00 to 900. It was concluded that the proposed design can be specifically viable for some important applications such as ‘THz’ images, filtering, biological sensing, and optical communications.