Electronic Circuit Elements Research Articles

Novel functional copolymer: Design, synthesis, click chemistry modification, and evaluation of dielectric and thermal properties

In this study, the modification of new polymers carrying dipeptide side groups with chalcone and their electrical properties were investigated. Therefore, initially, the phenylalanine dipeptide (Tyr(Boc)-Phe–OCH3) was synthesized. The ester group in the structure of this compound was converted to carboxylic acid to obtain the Boc-Tyrosine Phenylalanine-OH (Tyr(Boc)-Phe-OH) compound. This compound reacted with propargyl amine (PA) to synthesize (Tyr(Boc)-Phe-PA), which subsequently reacted with methacryloyl chloride to produce the methacrylate monomer (MA-Tyr(Boc)-Phe-PA). The polymerization of the prepared methacrylate monomer was carried out using the free radical polymerization method. In the final step, the active alkyne-terminated homopolymer reacted with the azide-terminated (4-Cl-CF3 N3-Chalcone) under copper catalysis through a click reaction, resulting in the synthesis of poly(MA-Tyr(Boc)-Phe-click-chalcone). The thermal behaviors of the polymers were determined using DSC and TGA thermal analysis methods. The initial decomposition temperature of the polymer was found to be 207.05 °C, whereas this value was 188.53 °C for the P(MA-Tyr(Boc)-Phe-click-chalcone) polymer. Additionally, the temperatures corresponding to a 50 % mass loss were 383.79 °C for the P(MA-Tyr(Boc)-Phe-PA) polymer and 394.78 °C for the P(MA-Tyr(Boc)-Phe-click-chalcone) polymer. The dielectric constant of the P(MA-Tyr(Boc)-Phe-PA) polymer was calculated to be 8.98, while the dielectric constant of the modified polymer obtained after click modification was calculated to be 13.87. The increase in the dielectric constant is thought to be due to the greater polarization of the triazole ring formed by the click reaction under an electric field. Furthermore, the AC conductivities of the compounds were calculated to be 5.00 × 10−9 S/cm and 1.11 × 10−9 S/cm at 1 kHz. When the dielectric properties of these two compounds are compared, the second polymer exhibits better polarization in an electric field, indicating its potential use as an electronic circuit element.

Electric-Field Control of the Local Thermal Conductivity in Charge Transfer Oxides.

Phonons, the collective excitations responsible for heat transport in crystalline insulating solids, lack electric charge or magnetic moment, which complicates their active control via external fields. This presents a significant challenge in designing thermal equivalents of basic electronic circuit elements, such as transistors or diodes. Achieving these goals requires precise and reversible modification of thermal conductivity in materials. In this work, the continuous tuning of local thermal conductivity in charge-transfer SrFeO3-x and La0.6Sr0.4CoO3-x oxides using a voltage-biased Atomic Force Microscopy (AFM)tip at room temperature is demonstrated. This method allows the creation of micron-sized domains with well-defined thermal conductivity, achieving reductions of up to 50%, measured by spatially resolved Frequency Domain Thermoreflectance (FDTR). By optimizing the oxide's chemical composition, the thermal states remain stable under normal atmospheric conditions but can be reverted to their original values through thermal annealing in air. A comparison between Mott-Hubbard and charge-transfer oxides reveals the critical role of redox-active lattice oxygen in ensuring full reversibility of the process. This approach marks a significant step toward fabricating oxide-based tunable microthermal resistances and other elements for thermal circuits.

Inverse design of ultrawideband one-dimensional metamaterial photonic filters using Riccati equation constrained gradient descent.

One-dimensional photonic wave devices exhibit a pivotal role in wave engineering. Despite their relative simplicity, designing 1D wave devices that implement complex functionalities over a broad frequency range is challenging and requires careful sculpting and multiple optimizations. This paper theoretically and experimentally demonstrates a new inverse design paradigm to achieve a desired broadband frequency response efficiently. Specifically, we calculate the required dielectric profile along the device using constrained gradient descent optimization to minimize the L 2 norm between the desired and actual responses. In each optimization step, we avoid the need to solve the complete set of Maxwell equations by using Riccati's equation or its discrete ancestor as the optimization constraint for calculating the local reflection coefficient. Using this approach, we design several unorthodox filters, such as dual-band narrowband bandpass filters located within a wideband bandstop and ultrawideband first and second-order differentiators. The technique produces excellent results for ultrawideband frequency ranges, with very low computational complexity and, remarkably, with a single trivial guess for the optimization starting point. We experimentally implemented the two differentiator designs in radio frequencies using electronic circuit elements that comprise a metamaterial transmission line structure.

Design and Analysis of a Group of Correlative and Switchable Dual Memristor Hyperchaotic Systems

In this paper, a group of correlative and switchable dual memristor hyperchaotic systems consisting of three subsystems is constructed. The common part of the systems is composed of charge-controlled memristor, capacitor and inductor. The switchable parts of the systems are composed of three different flux-controlled memristors. By switching the selection switch, different flux-controlled memristors can be selected to form different subsystems. The chaotic dynamics analysis show that the three subsystems all can be in the hyperchaotic state within the same parameter range. The equivalent analogy electronic circuit of charge-controlled memristor, three flux-controlled memristors, and the whole switchable system are designed. The circuit simulation results are consistent with the numerical simulation results, proving the physical feasibility of the correlative and switchable dual memristor hyperchaotic systems. The structure of the switchable system is simple and easy to implement through electronic circuit elements. One circuit can achieve the functionality of multiple hyperchaotic systems by switching the selection switch. This provides new ideas for integration of chaotic circuits and their applications in the fields of information security, random number generator, signal detection, etc.

Dynamics of a Photochromic-Actuated Slot Microring Photonic Memristor

In electronic circuits, memristors have been defined as resistors whose resistance depends on past signals. Such elements have promise as low-power weighting and self-learning elements in electronic neuromorphic circuits. Photonic memristors, elements whose transmission depends on past optical signals, are experiencing renewed study alongside the rise in interest in neuromorphic photonics. One potential route to creating photonic memristors involves incorporating photochromic materials, whose optical properties continuously change with optical illumination, into photonic integrated circuits (PICs). In this manuscript we lay out a theoretical model to study the transmission dynamics of devices incorporating photochromic compounds into SiN planar microring resonators which utilize slot waveguide structure, and show that such devices fulfill the criteria for memristive behaviour. This represents a practical path towards incorporating photonic memristors into a technologically mature material platform with minimal additional fabrication processes.

Engineering Transistorlike Optical Gain in Two-Dimensional Materials with Berry Curvature Dipoles.

Transistors are key elements of electronic circuits as they enable, for example, the isolation or amplification of voltage signals. While conventional transistors are point-type (lumped-element) devices, it may be interesting to realize a distributed transistor-type optical response in a bulk material. Here, we show that low-symmetry two-dimensional metallic systems may be the ideal solution to implement such a distributed-transistor response. To this end, we use the semiclassical Boltzmann equation approach to characterize the optical conductivity of a two-dimensional material under a static electric bias. Similar to the nonlinear Hall effect, the linear electro-optic (EO) response depends on the Berry curvature dipole and can lead to nonreciprocal optical interactions. Most interestingly, our analysis uncovers a novel non-Hermitian linear EO effect that can lead to optical gain and to a distributed transistor response. We study a possible realization based on strained bilayer graphene. Our analysis reveals that the optical gain for incident light transmitted through the biased system depends on the light polarization, and can be quite large, especially for multilayer configurations.

A Common Capacitor Hybrid Buck-Boost Converter

DC-DC converters are electronic circuit elements that are frequently used to change the direct current (DC) level. This paper presents a hybrid buck-boost converter - with constant modulation index - that can change a DC voltage at two directions compared to the conventional buck-boost DC-DC converters. First, the circuit structure and operation are given. Then, the performance of the proposed converter is tested on resistive and inductive loads, and compared with that of conventional buck-boost converters. The obtained results demonstrate the effectiveness of the proposed converter. They unveil that the proposed converter - compared to the conventional buck-boost converters – produces a higher and flexible rate of conversion without changing the operating ratio of the switches. Moreover, the proposed converter is able to change the voltage on double way on load for a constant operating ratio, while the traditional converters provide a one-way conversion.

Investigation of electrical performances of textile conductive lines under different connector configurations and external influences

As textile electronics has undergone a boom in the past few decades, especially the sensing aspect, methods of modular connectivity of these components with classical electrical components and printed circuit boards must be broadened. This study focuses on the aforementioned problem, as well as testing the electrical properties of conductive textile lines through a series of experiments. Fabrication of the conductive structure was done in two parts: embroidery of the conductive threads onto cloths, as well as designing and three-dimensional printing of connectors that will be used for bridging and making a stable connection with pin-based systems. A valid connection between the textile endings and pins has not yet been tested, and is the main focus of this paper, aside from testing outside influences on the designed textile structure. Afterwards, the developed prototype was tested through a realistic scenario that consisted of body temperature validations and the application of artificial sweat, as well as the quantification of the effects of washing on the electrical properties of the device. The outcome shows changes in the impedance modulus after washing. However, after application of artificial sweat, the nature of the parallel wire connections changes significantly, as the sweat acts as a resistive contact between the two wires. This examination can contribute to the field of wearable electronics through the proposed elements (conductive lines and connectors) of future electronic circuits in the concept of internet of bodies.

Strain Tunability of Perpendicular Magnetic Anisotropy in van der Waals Ferromagnets VI3.

Layered ferromagnets with strong magnetic anisotropy energy (MAE) have special applications in nanoscale memory elements in electronic circuits. Here, we report a strain tunability of perpendicular magnetic anisotropy in van der Waals (vdW) ferromagnets VI3 using magnetic circular dichroism measurements. For an unstrained flake, the M-H curve shows a rectangular-shaped hysteresis loop with a large coercivity (1.775 T at 10 K) and remanent magnetization. Furthermore, the coercivity can be enhanced to a maximum of 2.6 T under a 3.8% external in-plane tensile strain. Our DFT calculations show that the increased MAE under strain contributes to the enhancement of coercivity. Meanwhile, the strain tunability on the coercivity of CrI3, with a similar crystal structure, is limited. The main reason is the strong spin-orbit coupling in V3+ in VI6 octahedra in comparison with that in Cr3+. The strain tunability of coercivity in VI3 flakes highlights its potential for integration into vdW heterostructures.

Method for describing signal conversion processes in analog electronic systems

One of the main tasks of information technology is to improve existing and develop new methods for formal recording of various dynamic logical operations of analog and digital signal conversion in electronic control systems, acquisition, and processing of information. The stage of formal recording of any signal transformation process must be presented in the form of analytic symbols, the sequence of which must form a fully functional mathematical model. The improved method of the signals conversion processes description based on a representation of the mathematical models of the electronic circuits’ components in the grapho-analytical form with the increased information content allows integrating the developed models of electronic circuit elements with object-oriented programming language in the form of functional structures. It opens the way to perform parametric analysis of circuits and other tasks, related to the modeling of electronic systems.

Coordination-driven opto-electroactive molecular thin films in electronic circuits

An electrochemical method is utilized to prepare terpyridine layers on ITO, taking advantage of layer-by-layer deposition, growing opto-electro-active coordination compounds for the fabrication of electronic devices and circuit elements.

Decision trees within a molecular memristor.

Profuse dendritic-synaptic interconnections among neurons in the neocortex embed intricate logic structures enabling sophisticated decision-making that vastly outperforms any artificial electronic analogues1-3. The physical complexity is far beyond existing circuit fabrication technologies: moreover, the network in a brain is dynamically reconfigurable, which provides flexibility and adaptability to changing environments4-6. In contrast, state-of-the-art semiconductor logic circuits are based on threshold switches that are hard-wired to perform predefined logic functions. To advance the performance of logic circuits, we are re-imagining fundamental electronic circuit elements by expressing complex logic in nanometre-scale material properties. Here we use voltage-driven conditional logic interconnectivity among five distinct molecular redox states of a metal-organic complex to embed a 'thicket' of decision trees(composed of multiple if-then-else conditional statements) having 71 nodes within a single memristor. The resultant current-voltage characteristic of this molecular memristor (a 'memory resistor', a globally passive resistive-switch circuit element that axiomatically complements the set of capacitor, inductor and resistor) exhibits eight recurrent and history-dependent non-volatile switching transitions between two conductance levels in a single sweep cycle. The identity of each molecular redox state was determined with in situ Raman spectroscopy and confirmed by quantum chemical calculations, revealing the electron transport mechanism. Using simple circuits of only these elements, we experimentally demonstrate dynamically reconfigurable, commutative and non-commutative stateful logic in multivariable decision trees that execute in a single time step and can, for example, be applied as local intelligence in edge computing7-9.

Kinetic theory of monochromatic waves bunching in a low-voltage beam discharge in rare gases

The kinetic theory of phase focusing, that is bunching in a low-voltage beam discharge in rare gases (LVBD) during the propagation of longitudinal electrostatic oscillations at the Knudsen numbers of the order of unity have developed. The anomalous relaxation of the almost monoenergetic electron beam in momentum and energy is described for the case when this process cannot be explained by electron–atom collisions. The paper has shown the important role of electrons that have the beam energy and isotropic directional distribution, which is formed as a result of elastic collisions between the beam electrons and atoms. The dependence of the anomalous relaxation length on parameters of the LVBD in rare gases is studied.The developed theory makes it possible to quantitatively interpret experimental data on the LVBD under conditions when the electron mean free path is of the order of the interelectrode gap. According to these data, regardless of the density of the charged particles in the LVBD plasma in rare gases, five Langmuir plasma wavelengths fit along the length of the anomalous relaxation of the electron beam. The study of the electron beam dynamics laws in a plasma is important for the development of plasma-electrical devices, where the beam discharge is applied, namely: widely used all-movable stabilizers, sources of intense electromagnetic radiation, controlled elements of electronic circuits, plasma chemical reactors, etc.

The outlook for multivibrator application in the present day electronic systems

The paper discusses challenges that the present-day electronic industry of the Russian Federation faces today, analyses reasons for lagging in this sector in volume and production scale of the finished products in comparison to the leading in this area countries, suggests ways for reaching a new level in this industry by implementing a nationwide digitalization, reviews a place of digital signals in modern-day electronic, their types, creation methods, main characteristics, devices for generation and processing. The method of digital signals forming using the multivibrator was suggested in this paper. Different multivibrator types were reviewed, including the multivibrator with AND-NOT gates, its advantages were considered in comparison with the transistor stage multivibrators, parameters of the electronic circuit elements in the AND-NOT gate multivibrator for generating a signal with the required characteristics were calculated, then the multivibrator was assembled and the output signal parameters were taken down. The output signal parameters and the calculated parameters were identical. The conclusion was made about the possibility of the suggested AND-NOT gate multivibrator application in the complex automatic control circuits and electronic systems indication circuits as a device that generates signals with the required parameters.

Study of robin condition influence on phonon nano-heat conduction using meso-scale method in MOSFET and SOI-MOSFET devices

Metal oxide semiconductor field effect transistor (MOSFET) is a major element of electronic device circuits due to its ability to control the electrical signal. On the other hand, the size of this device became smaller, reached nanoscale. Several macroscopic theoretical studies have been documented on the importance of the thermal behavior in these nano-transistors. This paper provides a developed approach to study the nano-heat conduction coupled with Robin boundary condition and temperature jump boundary condition in MOSFET and Silicon on Insulator (SOI) MOSFET using the mesoscopic Boltzmann transport equation. The results indicated that there was a positive relationship between the increasing of inverse thermal resistance (Rth−1) and the reducing temperature in the source/drain for both devices while the maximal temperature at the interface semiconductor-wall decreases slightly for Rth−1=1010 W/m²∙K at t= 30 ps reaching 331.7 K for MOSFET and 338.5 K for SOI-MOSFET. The effect of heat generated in the active channel is more profound than the effect of Robin condition for Rth−1=107, 108, and 109 W/m²∙K at t = 10 ps. The most obvious findings to emerge from this study is that Robin boundary condition has a slight impact on heat along the channel region at a short time. In addition, this study identified the effect of layer oxide, which stores the heat between the source and the drain.

ОПТИМИЗАЦИЯ РАЗМЕЩЕНИЯ РАВНОГАБАРИТНЫХ ЭЛЕМЕНТОВ РЭА МОДИФИЦИРОВАННЫМ МЕТОДОМ ПОКООРДИНАТНОГО СПУСКА

The problem of optimal placement of elements of electrical and electronic circuits is considered. The minimum weighted connection length is selected as the criterion. A computational method is proposed that is a modification of the coordinate descent method and one of the variants of the General approach based on pair permutations. The scheme is defined by the connection matrix. We consider a fixed set of element positions and a distance matrix based on an orthogonal metric. This problem is a variant of the General mathematical model, called the quadratic assignment problem. Geometric restriction of the problem – no more than one element can be placed in one cell. It is stated that approaches based on paired and similar permutations are economical, and the method of the penalty function leads to” ditching ” and is ineffective. A modified coordinate descent method is described, which is a variant of the pair permutation method, in which pairs are selected based on the coordinate descent method. In the proposed version of the coordinate descent method, two coordinates are changed simultaneously at one stage of calculations (and not one, as in the usual optimization method). one of the coordinates is used for the usual trial step, and the other is used for correction, returning to the acceptable area. Next, the value of the target function is calculated at the found point and compared with the previously reached value. If the value has improved, the found point becomes the new starting point. Otherwise, a step is made on a different coordinate with simultaneous correction of the vector of item position numbers (return to the allowed area). The experience of using the modified method in solving the problem of placing EVA elements has shown its significant advantages in comparison with other known methods, for example, the genetic algorithm, as well as the method of penalty functions. An example of calculations using the proposed method is considered. The connection matrix was set analytically. First, the initial approximation was searched by the Monte Carlo method (10,000 iterations), after which the local optimum was calculated using a modified method of coordinate descent in the permutation space without repetitions (a limit of 100 iterations was set). The initial value of the coordinate step is equal to the size of the permutation, then at each iteration it was reduced by 1 to the minimum possible value of 1. The advantage of this method is that there is no penalty function. The search is performed automatically in the permutation space without repetitions. Computational experiments have shown high computational qualities of the proposed method.

Компьютерная оптимизация размещения элементов электронных цепей

The problem of optimal placement of elements of electrical and electronic circuits is considered. The minimum weighted length of the connections is selected as the criterion. The scheme is defined by a matrix of connections. We consider a fixed set of element positions and a distance matrix based on an orthogonal metric. This problem is a variant of the general mathematical model, called the quadratic assignment problem. The geometric limitation of the problem is that no more than one element is placed in one cell. Combinatorial analogs of the Gauss-Seidel method, the genetic algorithm, and the corresponding hybrid methods for solving the quadratic assignment problem with optimal placement of electronic equipment elements are developed and implemented on a computer. A series of computational experiments was conducted, which showed satisfactory computational qualities of the proposed methods. The proposed computational method, which is a combinatorial analog of the method of coordinate descent and one of the variants of the general approach based on paired permutations, is characterized by the best computational qualities among the methods studied in the article. According to well-known studies, the genetic algorithm is obviously no worse than the Monte Carlo method. The research conducted in the article shows that the method of penalty functions in the problem of placement and for the case of a genetic algorithm is ineffective. Therefore, it is of interest to consider permutations without repetitions as individuals of the population. This circumstance is taken into account at the stages of selection and mutation: at these stages, the standard calculations according to the genetic algorithm are supplemented by the procedure of paired rearrangements of genes in the chromosome. The article provides a detailed description of the program for the implementation of the genetic method on a computer.

Automation Software for Semiconductor Research Laboratories: Measurement System and Instrument Control Program (SeCLaS-IC)

Metal–semiconductor (MS) contacts are main aspects of almost all electronic circuit elements. Thus, contact mechanism and its electrical properties to develop a faster and more reliable electronic device should be known. The electrical characterization of MS devices (in terms of temperature-dependent and/or independent current–voltage (I–V), capacitance–voltage (C–V) and capacitance–frequency (C–f) measurements) is applied frequently in methods for determining the electrical properties and how it works and what the possible applications are. We prepared a program for basic electrical measurements and parameter extraction from these measurements of MS contacts. It is important to prepare and use such a program for a research laboratory, because electrical measurements must be made quickly after the production process and users should be able to carry out this process easily. This work can be discussed in two separate sections. The first section consists of a measurement system, automated instrument control program and data acquisition program (SeCLaS-IC Semiconductors Laboratory Software—instrument control). The second section is data evaluation and basic electrical parameter extraction program (SeCLaS-PC Semiconductors Laboratory Software—parameter calculation). In this paper, we discussed temperature-dependent current–voltage (I–V–T), capacitance–voltage (C–V–T) and capacitance–frequency (C–V–f) measurement system and instrument control program. This system is comprised of controlling program, liquid nitrogen (LN2)-cooled handmade cryostat system, temperature measurement system, and Keysight B2912A Precision Source/Measure Unit (SMU) and Keysight E4980A Precision LCR Meter. All programs were developed using Keysight VEE Pro (Visual Engineering Environment) software (Formerly Agilent VEE Pro).

Matlab Based Electrical Circuit Simulation Of Hodgkin-Huxley Neuron Model

Sinir hücrelerinin çalışmasını anlamak, fizyolojik özelliklerini ve davranışlarını incelemek için geliştirilen Hodgkin-Huxley, FitzHugh-Nagumo, Morris-Lecar, Hindmarsh-Rose, Izhikevich, Integrate & Fire ve Adaptive Exponential Integrate-Fire gibi birçok modelleme mevcuttur. Bu nedenle özellikle son yıllarda nöron yapısı, davranışı ve nöronlar arası fenomenler üzerine yapılan çalışmalar önemli bir alan haline gelmiştir. Nöron fizyolojisinin ve davranışlarının daha iyi anlaşılması için Hodgkin-Huxley (HH) nöron modeli, nümerik metotlar ile birçok kez simüle edilmiştir. Fakat literatür incelendiğinde Hodgkin-Huxley nöron modelinin elektriksel eş devresinin simüle edilmediği görülmüştür. Bu çalışmada, Hodgkin-Huxley nöron modeli eşdeğer devresi temel alınmış ve MATLAB/Simulink ortamında temel elektronik devre elemanları kullanılarak, nümerik metot benzetimlerinde kullanılan parametre değer aralıkları ile simüle edilmiş ve aksiyon potansiyelinin sadece dinlenme aşamasının oluştuğu diğer aşamaların oluşmadığı gözlemlenmiştir. Ancak devreye uygulanan uyarı akımı ve devrenin kapasite parametreleri değiştirildiğinde aksiyon potansiyelinin dinlenme, depolarizasyon ve repolarizasyon aşamalarının oluştuğu fakat hiperpolarizasyon durumunun tam olarak oluşmadığı gözlemlenmiştir. Böylece, nöron elektriksel eş devresinin oluşturduğu membran geriliminin, uyarı akımlarıyla ve kapasitans değerleriyle doğrudan ilişkili olduğu anlaşılmıştır.

Synthesis and characterization of poly(EGDMA-co-VPCA)/SWCNT composite films by surface polymerization method

Poly (EGDMA–co-VPCA)/SWCNT composite materials were produced on ITO coated glass substrates by surface polymerization method. Physical facilities of the deposits were studied by some techniques and approximation methods such as FTIR, SEM, EDS, MS and EIS. FTIR analyses confirm the formation of poly (EGDMA–co-VPCA)/SWCNT composite film. SEM studies show that the SWCNTs are embedded into the EGDMA-co-VPCA polymer. Semiconducting parameters, such as acceptor density, donor density, flat band voltage, positions of the valence and conduction energy band edge of the poly (EGDMA-co-VPCA)/SWCNT film are obtained by use of the Mott-Schottky and optical measurements. Mott-Schottky curves show that poly (EGDMA-co-VPCA)/SWCNT composite material exhibits both n-type and p-type conductivity depending on the applied potential. The EIS data were collected from poly (EGDMA-co-VPCA)/SWCNT/ITO/electrolyte system at a frequency range between 0.01 Hz and 300 kHz. Therefore, an equivalent electronic circuit model was fitted to the EIS data or Nyquist data. After the determination of the electronic circuit elements, charge transfer properties between electrolyte and composite polymer are also discussed from the standpoint of solution resistance, charge transfer resistance and constant phase element.