Plasmonic Refractive Index Sensor Based on Resonant System with Two Plasmonic Waveguides, Two Rings and Two Cavities

In this research, we seek to design and numerically evaluate a refractive index sensor based on the resonant system with metal insulating waveguide (MIM) that includes a wide range of wavelengths. To design the structure of this sensor, we use two rings with different dimensions and two cavities and two plasmonic waveguides. The resonant wavelengths and the refractive index of the resonators have been studied and simulated by the finite difference time domain (FDTD) method, which directly obtains the Maxwell equations by proper separation in the two time and space domains (But all the diagrams in this article are obtained using MATLAB). We send an electromagnetic wave to the structure of the sensor we have designed to analyze the field distributions and the spectral response of the structural parameters. When the field distribution is in the same structure, the energy loss is reduced. To achieve the maximum field distribution in the structure, all dimensions must be optimal. Intensification of the surface plasmon at the boundary between a metal surface and the dielectric material (sensor structure and waveguides) will increase the electric field strength and correct the sensor performance. Nanoparticle surface plasmon resonance depends on five factors: size, shape, nanoparticle composition, particle distance, and refractive index of the nanoparticle environment. These five factors affect the wavelength and intensity of the peak. To measure sensor performance, it calculates factors such as resolution, transmission efficiency, adjustable range of wavelengths, S sensitivity coefficient, FOM, Q quality factor and quality factor and width factor at half maximum value (FWHM). To achieve a functional plasmonic sensor. This sensor is suitable for use in fully integrated circuits as well as for the detection of chemical, biological and biological materials due to its high resolution accuracy, low size, high FOM value and high sensitivity coefficient.

Linearizability of 2:−3 Resonant Systems with Quadratic Nonlinearities

In this paper, the linearizability of a 2:−3 resonant system with quadratic nonlinearities is studied. We provide a list of the conditions for this family of systems having a linearizable center. The conditions for linearizablity are obtained by computing the ideal generated by the linearizability quantities and its decomposition into associate primes. To successfully perform the calculations, we use an approach based on modular computations. The sufficiency of the obtained conditions is proven by several methods, mainly by the method of Darboux linearization.

Rapid frequency modulation in a resonant system: aerial perturbation recovery in hawkmoths

Centimetre-scale fliers must contend with the high power requirements of flapping flight. Insects have elastic elements in their thoraxes which may reduce the inertial costs of their flapping wings. Matching wingbeat frequency to a mechanical resonance can be energetically favourable, but also poses control challenges. Many insects use frequency modulation on long timescales, but wingstroke-to-wingstroke modulation of wingbeat frequencies in a resonant spring-wing system is potentially costly because muscles must work against the elastic flight system. Nonetheless, rapid frequency and amplitude modulation may be a useful control modality. The hawkmoth Manduca sexta has an elastic thorax capable of storing and returning significant energy. However, its nervous system also has the potential to modulate the driving frequency of flapping because its flight muscles are synchronous. We tested whether hovering hawkmoths rapidly alter frequency during perturbations with vortex rings. We observed both frequency modulation (32% around mean) and amplitude modulation (37%) occurring over several wingstrokes. Instantaneous phase analysis of wing kinematics revealed that more than 85% of perturbation responses required active changes in neurogenic driving frequency. Unlike their robotic counterparts that abdicate frequency modulation for energy efficiency, synchronous insects use wingstroke-to-wingstroke frequency modulation despite the power demands required for deviating from resonance.

A Plasmonic Refractive-Index Sensor Based Multiple Fano Resonance Multiplexing in Slot-Cavity Resonant System

In this paper, a sub-wavelength metal-insulator-metal (MIM) waveguide structure is proposed by using a cross-shape rectangular cavity, of which wings are coupled with two rectangular cavities. Firstly, a cross-shape rectangular cavity is placed between the input and output MIM waveguides. According to the mutual interference between bright and dark modes, three Fano resonant peaks are generated. Secondly, by adding a rectangular cavity on the left wing of the cross shaped one, five asymmetric Fano resonance peaks are obtained. Thirdly, six asymmetric Fano resonance peaks are achieved after adding another cavity on the right wing. Finally, the finite-difference-time-domain (FDTD) method and multimode interference coupled-mode theory (MICMT) are used to simulate and analyze the coupled plasmonic resonant system, respectively. The highest sensitivity of 1 000nm/RIU is achieved.

Band gap analysis of a three-mass locally resonant structure

A mass in a mass locally resonant system has been studied using a numerical and analytical method. This study is performed to compute the band gap and transmission coefficient of a mass–spring locally resonant system. A locally resonant structure is a periodic structure which exhibits negative effective properties in a certain frequency band and reveals band gaps below Bragg’s frequency. In this work, two substructures are attached with main mass so that the system will act as two masses in a mass system. It is found that the presented structure shows two band gaps below 500 Hz with negative effective properties. Addition of a third substructure with the main mass provides an additional band gap at low frequency. The position and width of band gaps can be tuned by changing the values of masses and stiffness.

Toroidal dipole excitation in cylindrically arranged dogbone metallic inclusions

A significant excitation of toroidal moments in cylindrically arranged dogbone metallic inclusions is validated and presented in this paper. The antiparallel poloidal currents excited on the front and back faces of the proposed cylindrical dogbone inclusions create strong magnetic field confinement at the center generating intense toroidal moments on the structure. The significant excitation of toroidal dipole moment causes an improvement in the scattering cross-section from the resonant system. The resonant mechanism is analyzed using the multipole scattering theory, and we used the scattering measurement techniques to characterize the structure experimentally in the microwave regime.

Research on Anti-Offset Characteristics of Static Wireless Charging for Electric Vehicles

The static wireless charging of electric vehicles is more convenient than traditional charging methods, but due to man-made parking will cause the coil to shift, which will cause the transmission power of the system to fluctuate and affect the stability of the system. Through the analysis of the traditional doublesided resonant system, it is found that it is more sensitive to the coupling coefficient k and the primary current will increase suddenly when k approaches zero. In order to solve these two problems, this paper compares four different resonance conditions and performs a large number of simulation experiments show that the antioffset performance of the system is the highest when both the primary and secondary sides are designed to be detuned, but a certain efficiency is sacrificed. When the bilateral detuned system is in the range of 2.4 times the coupling coefficient k, then the fluctuation of transmission power is less than 15%, and the maximum transmission efficiency is 58%. It has good anti-offset ability. And when k approaches zero, the primary current will not increase suddenly. The security performance of the system is greatly improved.

Arbitrarily high time bandwidth performance in a nonreciprocal optical resonator with broken time invariance

Most present-day resonant systems, throughout physics and engineering, are characterized by a strict time-reversal symmetry between the rates of energy coupled in and out of the system, which leads to a trade-off between how long a wave can be stored in the system and the system’s bandwidth. Any attempt to reduce the losses of the resonant system, and hence store a (mechanical, acoustic, electronic, optical, or of any other nature) wave for more time, will inevitably also reduce the bandwidth of the system. Until recently, this time-bandwidth limit has been considered fundamental, arising from basic Fourier reciprocity. In this work, using a simple macroscopic, fiber-optic resonator where the nonreciprocity is induced by breaking its time-invariance, we report, in full agreement with accompanying numerical simulations, a time-bandwidth product (TBP) exceeding the ‘fundamental’ limit of ordinary resonant systems by a factor of 30. We show that, although in practice experimental constraints limit our scheme, the TBP can be arbitrarily large, simply dictated by the finesse of the cavity. Our results open the path for designing resonant systems, ubiquitous in physics and engineering, that can simultaneously be broadband and possessing long storage times, thereby offering a potential for new functionalities in wave-matter interactions.