Composite Resonator Research Articles

SYNTHESIS OF NANOSCALED MAGNETIC MATERIALS ON THE BASIS OF OXIDE SYSTEMS AND MANUFACTURING OF NON-RECIPROCAL COMPOSITE ELEMENTS BASED ON THEM

Nanoscaled particles of nickel-zinc ferrites solid solutions were synthesized by the method of precipitation from aqueous solutions, as initial reagents were used nitrates solutions, namely Fe(NO3)3, Ni(NO3)2 and Zn(NO3)3. Cylindrical composite resonant elements in a form of systems “high-Q non-magnetic dielectric – magnetic film” were manufactured using synthesized particles. As a non-magnetic dielectric was used barium tetratitanate BaTi4O9 with a doping of ZnO. For this the film-forming suspension consisted of synthesized ferrite particles and photopolymer was prepared. The suspension was applied on the end face of the dielectric resonator and polymerized by the UV radiation. Magnetic field of electromagnet was applied to the composite resonators during the magnetic film polymerization process (parallel or normal to the resonators axis).
 Absorption spectra of composite resonators in the waveguide measuring cell under influence of an external magnetic field were obtained. Spectra confirm the opportunity to control the resonance frequency of the composite structure and energy absorption in it using the external permanent magnetic field. The tuning of composite resonators parameters was more efficient for the resonators with the film polymerized in the parallel to the resonator axis field. For the frequency shift and electromagnetic isolation were obtained the values of 71 MHz and 53 dB respectively but with a high “straight” energy losses in the area of ferromagnetic resonance. So, the measuring cell with the composite resonator located in it was simulated using an Ansys HFSS software. Respective absorption spectra were obtained. It is shown that it is possible to manufacture composite resonators with a needed for the practical applications characteristics level (reverse losses were 34 dB, straight losses were 0.8 dB) and a tuning ability for the development of superheterodyne transmitters, dynamic filters for microwave technics, microwave valves, etc.

Membrane-ring acoustic metamaterials with an orifice

This work proposes a modified acoustic metamaterial consisting of a membrane-ring structure and orifice. Addition of the orifice can create an extra transmission loss (TL) peak besides the one originated from the membrane-ring structure. Effective mass density and phase change at their characteristic frequencies are plotted to explain responsible physical mechanisms. Capabilities of tailoring these frequencies are also exhibited. When the proposed metamaterial is backed by a cavity containing air, it is even able to serve as a ventilated composite resonator outperforming conventional ones at low frequency regimes. Different mechanisms responsible for each TL peak are identified and clearly illustrated with air velocity profiles.

Controlling the Characteristics of the Magnetoelectric Effect in Composite Resonators through External Actions

The possibility of controlling the characteristics of the low-frequency resonant magnetoelectric effect in composite structures using external effects is demonstrated. These composite structures contain ganged ferromagnetic and piezoelectric layers. The magnitude of the magnetoelectric effect in planar structures with layers of nickel and lead zirconate titanate changes by tens of percent, and the frequency of acoustic resonance is altered to ten percent under the action of a constant magnetic field or a constant electric field when the temperature changes or mechanical stresses are created in the structure.

Composite circular split ring resonator (CSRR)-based left-handed metamaterial for C- and Ku-band application

The aim of this study is to introduce a compact metamaterial structure for dual-band (C- and Ku-band) applications. Due to their unique electromagnetic properties, metamaterials find wide use in satellite applications to improve performance, and have therefore received great attention from researchers all over the world. In this article, a left-handed circular split ring resonator metamaterial structure is designed for satellite application. The inner circular split rings are split with thickness of 0.20 mm and a 0.25 mm thickness rectangular bar tilted at angles of 0°, 90°, 180° and 270° to connect all the main resonator rings. The metamaterial design proposed here is developed on a square Epoxy Resin Fiber (FR-4), which serves as the dielectric substrate layer. The metamaterial structure was successfully designed and simulated using numerical analytical methods such as Finite Integration Technique (FIT)-based electromagnetic simulator, and Computer Simulation Technology Microwave Studio (CST). Several designs were used to perform parametric studies while varying the subtract strip line thicknesses and subtraction angles. A frequency range of 0–18 GHz was used in simulation, where the design manifested resonance frequencies at 6.46 GHz and 16.92 GHz. In addition, the fabricated metamaterial showed resonance frequencies at 6.54 GHz and 17.06 GHz, making this design applicable for both C- and Ku-bands. Comparison between experimental and numerical results showed that transmission coefficient graphs obtained from the two methods were largely in agreement with each other and showed only small differences. The resonance frequency at Ku-band exhibited left-handed metamaterial behavior that makes the designed metamaterial suitable for satellite communication system.

Development and Study of Composite Acoustic Resonators with Al/(Al, Sc)N/Mo/Diamond Structure with a High Q Factor in the UHF Range

Development and Study of Composite Acoustic Resonators with Al/(Al, Sc)N/Mo/Diamond Structure with a High Q Factor in the UHF Range

Evidence for complete low-frequency vibration band gaps in a thick elastic steel metamaterial plate

Elastic steel metamaterial plates can be used for noise- and vibration-reduction due to unique physical properties related to their vibration band gap. However, obtaining a complete low-frequency vibration band gap in a thick elastic steel metamaterial plate is difficult. In this paper, we simulate a complete low-frequency vibration band gap in a thick elastic steel metamaterial plate. The structure consists of periodic, double-sided, composite stepped resonators, which were deposited on a 2D locally resonant phononic crystal plate. The phononic crystal plate consists of an array of rubber fillers embedded in a thick steel plate. The dispersion relations, power-transmission spectra, and the displacement fields of the eigenmodes are calculated using the finite-element method. The results show that, for the proposed structure, the opening of the first complete vibration band gap is reduced by a factor of 9.5 compared to a conventional thick elastic steel metamaterial plate. This causes attenuation of low-frequency elastic waves. The formation mechanisms for the vibration band gap are also explored numerically. The results indicate that the formation mechanism for the new low-frequency vibration band gap can be attributed to coupling between a local resonance mode of the composite stepped resonators and the Lamb wave mode of the thick steel-plate. The location of the vibration band gap is determined by the resonator mode of the composite stepped resonators. The vibration band gap effects of the composite stepped resonators are also investigated in this paper. We find that the location of the complete vibration band gaps can be modulated with a relatively low frequency using different composite stepped resonators. Such an elastic steel metamaterial plate with a complete low-frequency vibration band gap can be used to reduce both vibration and noise in various commercial and research applications.

Dual‐wideband filter with wide high‐rejection band using composite resonators

A new type of dual-wideband bandpass filter using composite series and shunt resonators is proposed in conjunction with its direct synthesis and design theory. By making use of the transmission pole (TP) and the transmission zero of the composite resonators flexibly, a dual-wideband filter with a wide range of frequency and bandwidth ratios as well as a wide stopband can be realised. With a shunt capacitor introduced at each I/O port, extra TPs either in the low passband or in the high passband can be created, leading to more filter design options. To give a direct design procedure, a lumped-element prototype is first synthesised based on a target filtering function and a dedicated circuit extraction process. The filter layout can be realised using semi-distributed circuits and chip capacitors. Two practical schemes are introduced to suppress spurious resonances for a wide high-rejection stopband. Two filter examples are designed with a small and a large frequency ratio and a wide band suppressed spurious resonances. The unique filter response and good agreement between the designed and measured results demonstrate the superior performance of the proposed filter structure and the effectiveness of the synthesis and design theory.

A Novel Design Method for High Isolated Microstrip Diplexers Without Extra Matching Circuit

A novel design method of microstrip diplexer without extra matching circuit is proposed in this paper. Because of the synthesizable circuit parameters and controllable transmission zeros (TZs) in composite resonator (CR) cell, diplexer A based on CR cell is proposed. By allocating TZs at center frequency of the opposite channel, as well as the using of impedance transformations of J inverters, high isolation and good passband selectivity are realized in diplexer A without extra matching circuit. In order to improve the stopband performance, diplexer B based on coupled CR cells is proposed. Furthermore, diplexer B using the proposed design method is implemented by directly combining two bandpass filters (BPFs), which simplifies significantly the design process of diplexers. Diplexer A operated at 1/1.2 GHz and diplexer B operated at 1/1.5 GHz are designed and fabricated. The measured isolation characteristics in diplexer A and diplexer B are all higher than 40 dB. Good agreements between simulated and measured results are achieved, which successfully verifies the proposed design method of diplexers.

Data Correction for Surface Nuclear Magnetic Resonance in an Inhomogeneous Geomagnetic Field

In surface nuclear magnetic resonance, the geomagnetic field serves as the background field, and hydrogen protons in groundwater are excited with an alternating field at the Larmor frequency. However, in practice, an inhomogeneous geomagnetic field (IGF) or a magnetic anomaly caused by ferromagnetic materials will make the Larmor frequency nonunique, resulting in simultaneous on-resonance and off-resonance signals (composite resonance). If only the onresonance or off-resonance model is used to interpret the composite resonance data, the accuracy of the inversion analysis would be adversely affected. To solve this problem, we derived an expression for the composite magnetic-resonance free-induction-decay (FID) signal based on a layered model. The influence of IGF on the characteristic parameters of the FID signal was analyzed with simulation models, which showed that, with an increase in frequency offset and gradient, the relaxation time decreased prominently. We demonstrate an iterative correction method based on a frequency-depth curve. Through simulated and measured data, we show that the water content and relaxation time are consistent with ground truth after correction and that data consistency is improved.

Prospects of searching for composite resonances at the LHC and beyond

Composite Higgs models predict the existence of resonances. We study in detail the collider phenomenology of both the vector and fermionic resonances, including the possibility of both of them being light and within the reach of the LHC. We present current constraints from di-boson, di-lepton resonance searches and top partner pair searches on a set of simplified benchmark models based on the minimal coset SO(5)/SO(4), and make projections for the reach of the HL-LHC. We find that the cascade decay channels for the vector resonances into top partners, or vice versa, can play an important role in the phenomenology of the models. We present a conservative estimate for their reach by using the same-sign di-lepton final states. As a simple extrapolation of our work, we also present the projected reach at the 27 TeV HE-LHC and a 100 TeV pp collider.

The application of compound proportional resonant control strategy in multiple PV inverters system

In order to eliminate the effect on the grid current caused by the background harmonic voltage and the reference signal on the grid connected multi-inverter, this paper adopts the double closed-loop feed-forward control strategy. This strategy is based on the inductor voltage and the grid-connected current, and the integrated control strategy of quasi-proportional resonance loop parallel to a specific harmonic compensation loop. Based on the closed-loop model of multiple inverters, the change curves of the transfer function of the two control strategies are compared with the feed-forward control and the composite proportional resonance. The two corresponding control methods are used to analyze the current quality of the multi-inverter impact. Finally, the MATLAB/Simulink simulation model is set up to verify the proposed control strategies. The simulation results show that the proposed method can achieve better tracking of the sinusoidal command signal at the fundamental frequency, and enhance the anti-interference ability of the system at the 3rd, 5th, and 7th harmonic frequency.

An electric field controlled dual resonator magneto‐electric band‐stop filter

AbstractA band‐stop filter with dual resonators of yttrium iron garnet (YIG) and lead zirconate titanate (PZT) operating in the S‐ and C‐bands was designed and characterized. Such multiferroic composite resonators allow for mechanical strain mediated control of the ferromagnetic resonance frequency of YIG via a DC voltage applied to PZT. The electric field E‐tuning of the central frequency of the individual resonators by 65‐70 MHz has been utilized for the control of the isolation characteristics by 17 dB and to achieve a maximum transmission loss of 37 dB. The 3 dB‐width of the stop‐band can also be tuned between 40 and 100% when a DC voltage is applied to only one of the two resonators. Such E‐tuning of filter characteristics are of interest for applications in communication systems.

Universal Imprints of a Pseudo-Nambu-Goldstone Higgs Boson.

A large class of models addressing the electroweak naturalness problem postulates the existence of new spontaneously broken global symmetries above the weak scale. The Higgs boson arises as a pseudo-Nambu-Goldstone boson (PNGB) whose interactions are nonlinear due to the presence of degenerate vacua. We argue that, once the normalization of the PNGB decay constant f is determined, the Higgs nonlinear interactions in the gauge sector are universal in the infrared and independent of the symmetry breaking pattern G/H, even after integrating out heavy composite resonances. We propose a set of "universal relations" in Higgs couplings with electroweak gauge bosons and in triple gauge boson couplings, which are unique predictions of the universal nonlinearity. Experimental measurements of these relations would serve as the litmus test of a PNGB Higgs boson.

Light-induced EPR study of spin-assisted charge transport in PFOT:PC61BM composite

Magnetic resonance, relaxation and dynamic parameters of polaron spins and methanfullerene radical anions, initiated by the infrared-visible-ultraviolet photons in bulk heterojunctions of the composite formed by narrow-band poly[(9,9-dioctylfluorenyl-2.7-diyl)-co-(bithiophene)] (PFOT, F8T2) copolymer and [6,6]-phenyl-C61-butyric acid methyl ester (PC61BM) globules were investigated by the direct Light-Induced Electron Paramagnetic Resonance (LEPR) spectroscopy. It was shown that some of the polarons are captured by spin traps formed in the copolymer matrix due to its disordering. The number, spatial distribution and energy depth of such traps depend on the structure and morphology of composite. It is shown that the main parameters of both charge carriers are determined by the exchange interaction of the spin ensembles, as well as the energy of the photons. The formation of spin traps in the copolymer matrix and the exchange interaction between different spin packets cause the extreme sensitivity of the composite's magnetic resonance and electronic parameters to the number and energy of the initiating photons. The predominant photoinitiation of localized polarons in the copolymer matrix was demonstrated. This process is substantially accelerated when the composite is illuminated by photons with the energy lying near 1.8 and 2.7 eV. The recombination of both charge carriers can be described in terms of a bimolecular process of the second order. It was found that the contributions of polarons and methanofullerene radical anions to the effective paramagnetic susceptibility increase substantially near the photon energy of 2.6 and 2.1 eV due to the exchange interaction of these charge carriers. It is shown that the mobility of polarons varies monotonically throughout all the photon energy range, whereas the librational spin dynamics of the methanofullerene globules is substantially accelerated near the photon energy of 2.0 and 2.7 eV.

Thermoelastic damping in trilayered microplate resonators

The design of laminated composite microplate resonators with high quality (Q) factors requires careful analysis of thermoelastic damping since it is an inherent intrinsic energy dissipation mechanism. This paper presents a temperature field in a general trilayered microplate with thermally perfect interfaces based on the integral transform approach. In addition, an analytical model to calculate thermoelastic damping in general trilayered fully clamped microplates is developed. Total thermoelastic damping for trilayered microplates can be expressed as a sum of the normalized energy dissipated in each layer. In order to validate the present model, the results calculated by the present model are compared with those calculated by finite element method (FEM). Our results show that the energy dissipation in the middle part is less than that in the outer parts for homogenous microplates. Thermoelastic damping peaks in trilayered microplates are discussed, which are associated with the critical damping frequency and the Zener's modulus of each layer. When the Zener's modulus of one layer is 2–3 orders of magnitude higher than that of another layer and the critical damping frequency of this layer is also 2–3 orders of magnitude higher than that of another layer, the thermoelastic dissipation spectrum will exhibit multiple peaks. It is also observed that the second layer may exhibit negative energy dissipation in SiC/Ti/Au and Si3N4/Si/Au trilayered microplates.

Electromagnetic field analysis of shielded composite dielectric spherical shell resonator in infrared and visible regions

In this paper, we have presented an electromagnetic field analysis of shielded composite dielectric spherical shell resonator. The resonator studied in this work is considered for the first time as no study on such resonators is available in the published literature to the best of the author's information. This shielded composite dielectric spherical shell resonator is composed of two concentric metal spheres with different dielectric material has been made. The whole assembly is shielded by a perfectly conducting concentric spherical metal. The expression for the resonant frequencies and quality factors have been calculated using numerical methods for both the TEnmℓand TMnmℓ modes for an infrared and visible regions. It is found that as the outer radius of the shielded composite dielectric spherical shell resonator increases, the quality factor Q of the resonator increases monotonically. It is also found that if we change the radius of the inner dielectric sphere, there is no appreciable change in resonant frequency of the concerned mode is observed. This is due to the small difference in the permittivities of the materials of the inner and the outer dielectric spheres. It has also been observed that an inner concentric superconducting sphere within a dielectric spherical resonator is a more effective controlling parameter of the resonant frequency than the other parameters.

Direct synthesis of compact wideband differential bandpass filter on composite triple-mode resonator

In this paper, a direct synthesis approach is proposed for design of a compact wideband differential-mode (DM) bandpass filter (BPF) on a composite triple-mode resonator. By virtue of intrinsic common-mode (CM) suppression in slotline portion, only the DM transmission performances need to be focused on in our design, so as to facilitate the design process. Consequently, a synthesis approach based on an equivalent simplified network is established to design this DM BPF, resulting to directly determine all the circuit element values. A wideband DM BPF is then designed to validate effectiveness of proposed synthesis method. Finally, two circuit prototypes have been designed, fabricated, and measured. The synthesized, simulated and measured results agree well with each other over a wide operating band, which has demonstrated the proposed DM BPFs' attractive performances, such as wide bandwidth of operation, sharpened frequency selectivity, and good CM suppression.

Microwave composite structures on the base of nickel-zinc ferrite Ni1−xZnxFe2O4 nanoparticles in the photopolymer matrix

The 3D printing compatible technology of “ferrite – nonmagnetic dielectric” composite structures preparation was proposed. Composite resonant elements for applications in the centimeter range of microwave frequencies comprising nonmagnetic dielectric BaTi4O9-ZnO and ferrite film made from spinel nickel-zinc ferrite Ni1−xZnxFe2O4 (x = 0; 0.25; 0.5; 0.75; 1) magnetic nanoparticles in the photopolymer matrix were manufactured.Microwave characteristics of the obtained composite resonators with different concentrations of ferrite nanoparticles in the film-forming suspension were investigated. It was shown, that magnetic field makes the influence on the transmission characteristics of composite resonators, namely the operating frequency, resonance linewidth and the resonant absorption level. The developed elements can be used to create the various microwave devices (solid-state oscillators, microwave filters and attenuators) with the magnetic field tunable parameters.

Behavior of composite resonances breaking lepton flavor universality

Within the context of composite Higgs models, recent hints on lepton-flavour non-universality in $B$ decays can be explained by a vector resonance $V$ with sizeable couplings to the Standard Model leptons ($\ell$). We argue that, in such a case, spin-$1/2$ leptonic resonances ($L$) are most probably light enough to open the decay mode $V \rightarrow L\ell$. This implies, in combination with the fact that couplings between composite resonances are much larger than those between composite and elementary fields, that this new decay can be important. In this paper, we explore under which conditions it dominates over other decay modes. Its discovery, however, requires a dedicated search strategy. Employing jet substructure techniques, we analyse the final state with largest branching ratio, namely $\mu^+\mu^- Z/h, Z/h \rightarrow$ jets. We show that (i) parameter space regions that were believed excluded by di-muon searches are still allowed, (ii) these regions can already be tested with the dedicated search we propose and (iii) $V$ masses as large as $\sim 3.5$ TeV can be probed at the LHC during the high-luminosity phase.

Dynamic Photoinduced Controlling of the Large Phase Shift of Terahertz Waves via Vanadium Dioxide Coupling Nanostructures

Utilizing terahertz (THz) waves to transmit data for communication and imaging places high demands on phase modulation. However, until now, it is difficult to realize a more than 100° phase shift in the transmission mode with one-layer structure. In this paper, a ring-dumbbell composite resonator nested with VO2 nanostructures is proposed to achieve the large phase shift. It is found that in this structure a hybrid mode with an enhanced resonant intensity, which is coupled by the L-C resonance and dipole resonance has been observed. Applying the photoinduced phase transition characteristics of VO2, the resonant intensity of the mode can be dynamically controlled, which leads to a large phase shift in the incident THz wave. The dynamic experimental results show that controlling the power of the external laser can achieve a phase shift of up to 138° near 0.6 THz using this one-layer VO2 nested composite structure. Moreover, within a 55 GHz (575–630 GHz) bandwidth, the phase shift exceeds 130°. This attracti...