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In this article, a 12 switch 31 L multi-level inverter (MLI) is proposed with the benefits of least switching devices for electric vehicle applications. In most electric vehicles (EV), conventional inverters are utilized so the lifetime of electric vehicle induction motors is reduced due to the high THD level and high voltage stress. To rectify this, a new inverter topology is proposed with minimum switching devices by increasing the level to 31, and also the THD should be maintained within IEEE standards. This inverter topology is constructed with variable DC sources (PV system) along with required capacitors and a polarity changer. The specific feature of this topology is that it can generate any level of voltage with minimum switching devices, less voltage stress, minimum THD, and less cost are tabulated in the comparison. This type of inverter can also applicable for high voltage (HV) applications and grid-connected systems. Furthermore, the proposed topology is simulated with MATLAB software and the downscale prototype model is developed using the DSPIC30f2010 controller. [ABSTRACT FROM AUTHOR]

Electric double layer effect in solid electrochemical systems is a key topic in energy storage applications. In this review, we outline recent investigations on the electric double layer effect of solid electrolyte interfaces by utilizing a semiconducting diamond surface as a probe of electrical charges at the solid/solid interfaces. Hall measurements with various solid electrolyte-based transistors evidenced that the electric double-layer effect strongly depends on the properties of the electrolyte and the very thin region from the interface. The unveiled features of the electric double layer at solid electrolyte interfaces are quantitatively discussed from the viewpoint of charge density and charging-discharging rate. Furthermore, applications of the unique switching response of the electric double layer transistors to neuromorphic computing are also demonstrated. [ABSTRACT FROM AUTHOR]

Nonreciprocal quantum transport effect is mainly governed by the symmetry breaking of the material systems and is gaining extensive attention in condensed matter physics. Realizing electrical switching of the polarity of the nonreciprocal transport without external magnetic field is essential to the development of nonreciprocal quantum devices. However, electrical switching of superconducting nonreciprocity remains yet to be achieved. Here, we report the observation of field-free electrical switching of nonreciprocal Ising superconductivity in Fe3GeTe2/NbSe2 van der Waals (vdW) heterostructure. By taking advantage of this electrically switchable superconducting nonreciprocity, we demonstrate a proof-of-concept nonreciprocal quantum neuronal transistor, which allows for implementing the XOR logic gate and faithfully emulating biological functionality of a cortical neuron in the brain. Our work provides a promising pathway to realize field-free and electrically switchable nonreciprocity of quantum transport and demonstrate its potential in exploring neuromorphic quantum devices with both functionality and performance beyond the traditional devices. The authors demonstrate magnetic-field-free electric switching of superconducting nonreciprocity in Fe3GeTe2/NbSe2 heterostructures. They apply this to propose and demonstrate a proof-of-concept "neural transistor", a tetrode device that realizes an XOR gate with only a single transistor. [ABSTRACT FROM AUTHOR]

Consumers may anticipate regret when making purchasing decisions on a battery-charging vehicle (CV) or a battery-switching vehicle (SV). They anticipate a revolutionary regret when purchasing SVs with an extra switching function but a higher price, and a conservative regret at a lower price but only a charging function. This study investigates whether and how anticipated regret affects competing manufacturers' price and quality. We find that SV demand is always higher than CV demand, and anticipated regret always promotes electric vehicle (EV) adoption. Interestingly, the revolutionary regret discourages the development of the extra battery-switching function and weakens the consumer's preference for SVs. Then, the presence of only revolutionary regret causes a lose–lose situation where SV manufacturers reduce the quality level of the additional battery-switching attribute and thus intensify price competition for both manufacturers. SV sales cannibalize CV demand when consumers anticipate revolutionary regret. Moreover, the presence of only conservative regret has no impact on SV manufacturers, but affects CV manufacturers. When EV charging is convenient for consumers, CV manufacturers benefit from conservative regret; otherwise, CV manufacturers quit the market. Finally, when two kinds of regret coexist, the profits of both manufacturers are lower than when there is no regret and only conservative regret, but they are higher than when there exists only revolutionary regret. The results not only contribute to guiding the manufacturer to invoke or mitigate consumers' anticipated regret, but also provide advice to show or hide this regret for consumers. [ABSTRACT FROM AUTHOR]

We extend a multimodal transport model to simulate an increase of the market share of electric vehicles. The model, which is described in detail in Kilani et al. (Sustainability 14(3):1535, 2022), covers the north of France and includes both urban and intercity trips. It is a multi-agents simulation based on the MATsim framework and calibrated on observed traffic flows. We find that the emissions of pollutant gases decrease in comparable proportion to the market share of the electric vehicles. When only users with shorter trips switch to electric vehicles, the impact is limited and demand for charging stations is small since most users will charge by night at home. When the government is able to target users with longer trips, the impact can be higher by more than a factor of two. But, in this case, our model shows that it is important to increase the number of charging stations with an optimized deployment for their accessibility. [ABSTRACT FROM AUTHOR]

Bismuth ferrite (BiFeO3) is a multiferroic material that exhibits both ferroelectricity and canted antiferromagnetism at room temperature, making it a unique candidate in the development of electric-field controllable magnetic devices. The magnetic moments in BiFeO3 are arranged into a spin cycloid, resulting in unique magnetic properties which are tied to the ferroelectric order. Previous understanding of this coupling has relied on average, mesoscale measurements. Using nitrogen vacancy-based diamond magnetometry, we observe the magnetic spin cycloid structure of BiFeO3 in real space. This structure is magnetoelectrically coupled through symmetry to the ferroelectric polarization and this relationship is maintained through electric field switching. Through a combination of in-plane and out-of-plane electrical switching, coupled with ab initio studies, we have discovered that the epitaxy from the substrate imposes a magnetoelastic anisotropy on the spin cycloid, which establishes preferred cycloid propagation directions. The energy landscape of the cycloid is shaped by both the ferroelectric degree of freedom and strain-induced anisotropy, restricting the spin spiral propagation vector to changes to specific switching events. Previous understanding of the coupling between ferroelectric structure and magnetic texture in BiFeO3 has relied on mesoscale measurements. Here, the authors image coupling directly, showing a complex spin cycloid controlled with electric field. [ABSTRACT FROM AUTHOR]

One from the most important features of relaxors is the possibility of inducing a stable ferroelectric phase in them by applying an electric field. This induced phase transition has been multiply investigated; in particular, the structural changes during the transition and its kinetics were traced. However, the processes occurring under electric field switching remain little-studied, and the structural transformation during switching generally has not been investigated at all. To fill in this gap, the temporal evolution of the pattern of Bragg and diffuse X-ray scattering in classical relaxor PbMg1/3Nb2/3O3 at T = 175 K during multiple switching of the direction of a dc external field E = ± 6.25 kV/cm has been traced. It is shown that the glasslike state decays and a mixed ferro-glass phase is formed after switched on a field. Switching the field sign leads to a rise of dipole-glass correlations; however, no signs of occurrence of an inhomogeneous state with limited regions of dipole-glass and ferroelectric phases were found. Switching the field to the initial direction causes rapid formation of the ferroelectric phase, without any rise in the dipole-glass correlations. A repeated switching leads to a decrease in the Bragg scattering intensity, related to the long-range order. This effect is presumably due to the occurrence of random weakly correlated ionic displacements, violating the long-range order. [ABSTRACT FROM AUTHOR]

The processes accompanying the formation of a contracted (columnar) high-current nanosecond electric discharge in subcentimeter gaps filled with nitrogen are numerically investigated in this work. The space between two flat electrodes is considered in the case when a potential difference of 25 kV is instantly established between them. The voltage is applied for a time interval of 200 ns and then instantly removed. The characteristics of the nonthermal and thermal stages of electric-discharge development are studied, namely: the formation and growth of a streamer, the closure of a discharge gap by a streamer, the formation of a plasma channel, secondary ionization waves, and an increase in current density and temperature in the axial region of the channel. After switching off the electric field, the gas-dynamic processes associated with the discharge thermal effect on a neutral gas are investigated. Gas-dynamic processes are determined by the propagation of shock waves and rarefaction waves in the radial direction with respect to the axis of symmetry. The quantitative values of both the electric field (electron density and intensity) and gas-dynamic parameters (temperature, pressure, and gas velocity) are determined. [ABSTRACT FROM AUTHOR]

The nature of molecule-electrode interface is critical for the integration of atomically precise molecules as functional components into circuits. Herein, we demonstrate that the electric field localized metal cations in outer Helmholtz plane can modulate interfacial Au-carboxyl contacts, realizing a reversible single-molecule switch. STM break junction and I-V measurements show the electrochemical gating of aliphatic and aromatic carboxylic acids have a conductance ON/OFF behavior in electrolyte solution containing metal cations (i.e., Na+, K+, Mg2+ and Ca2+), compared to almost no change in conductance without metal cations. In situ Raman spectra reveal strong molecular carboxyl-metal cation coordination at the negatively charged electrode surface, hindering the formation of molecular junctions for electron tunnelling. This work validates the critical role of localized cations in the electric double layer to regulate electron transport at the single-molecule level. A common approach to design single-molecule switch is to use molecular backbones in response to external stimulus, but often requires complex organic synthesis. Here, Tong et al. show how to in situ control of the molecule-electrode contact using electrochemical gating to realize a reversible switch. [ABSTRACT FROM AUTHOR]

In this study, fullerene C20 molecule was used and two types of molecular switch structures were designed. Then, using DFT calculations, the effect of electric fields, with powers of 0 to 100 × 10–4 a.u., on their structural and electrical properties was investigated. It was observed that with increasing electric field, the structure of switches 1 and 2 changes and the intensity of changes in dihedral angle is more than other structural parameters. Sudden changes in dihedral angle occur in the electric field, which can indicate that the switch is on. It was shown that as the electric field strength increases, the HLG decreases, which decreases sharply in a given field and then becomes constant. This fast decrease in HLG, which is in correspondence with changing in the dihedral angle, demonstrates the on state of the molecular switch. NBO Charges analysis on the Au, S, N, and O atoms shows that the electric field pushes the electrons toward more positive electric fields. Finally, the evidence shows that switch 1 in the electric field about 0.006 to 0.008 a.u. is switched from off to on, and switch 2 in the electric field is switched from 0.003 to 0.005 a.u. [ABSTRACT FROM AUTHOR]

The structure of Cd – Ag – N coatings deposited by electron-ion-plasma sputtering is studied. The hardness, the modulus of elasticity, the wear resistance, and the friction coefficient are determined. The coatings are shown to affect positively the combination of the operating properties of copper electric contacts of switches of high-power networks. [ABSTRACT FROM AUTHOR]

With the advent of the Internet of Things, nanoelectronic devices or memristors have been the subject of significant interest for use as new hardware security primitives. Among the several available memristors, BiFe O 3 (BFO)-based electroforming-free memristors have attracted considerable attention due to their excellent properties, such as long retention time, self-rectification, intrinsic stochasticity, and fast switching. They have been actively investigated for use in physical unclonable function (PUF) key storage modules, artificial synapses in neural networks, nonvolatile resistive switches, and reconfigurable logic applications. In this work, we present a physics-inspired 1D compact model of a BFO memristor to understand its implementation for such applications (mainly PUFs) and perform circuit simulations. The resistive switching based on electric field-driven vacancy migration and intrinsic stochastic behaviour of the BFO memristor are modelled using the cloud-in-a-cell scheme. The experimental current–voltage characteristics of the BFO memristor are successfully reproduced. The response of the BFO memristor to changes in electrical properties, environmental properties (such as temperature) and stress are analyzed and consistant with experimental results. [ABSTRACT FROM AUTHOR]

Electrochromic nanomaterial membrane (ENM) Device is fabricated utilizing sputter technique on ITO glass substrates integrating with Ag NW-doped WO3 as electrochromic film, PEO as electrolyte and H+Nb2O5 as counter electrode that grab intensified concept in smart applications mostly as switchable displays. Optical analysis of the newly developed and fabricated ENM Nanosystem device is examined and compared with the existing and analogous nanostructured devices of the era. The ENM device is observed to possess a peak bleaching transmittance of 91% at 515 nm, which is ~ 8% enriched in visible spectrum in contrast to the existing nanomaterial membrane device. Transmittance modulation of ENM is calculated to be 76.6%. The faster switching of the ENM for electric dimming is observed to hold with 25, 33 and 30 s of increment at 500, 550 and 600 nm, respectively. Also the voltage variation for the ENM is analysed over − 2 V to + 2.5 V that provide a detailed and spacious changing across the full spectrum range. The cyclic voltammetry (CV) measurement on the entire Nanocomposite ENM Device revealed contraction of current density due to carrier confinement effect by coagulation of both EC and counter electrode membranes and thereby the quantifiable Formal Reduction Potential of the device is acquired owing to simultaneous ion confinement as well as carrier transition. The electrochemical response of the two electrodes on ITO-coated glass substrate as well as the entire nanocomposite-based membrane device entail the novel ENM device to be an excellent solution with appropriateness and superior efficiency for smart applications and approaches. [ABSTRACT FROM AUTHOR]

With speeding up development of 5 G chips, high-efficient thermal structure and precise management of tremendous heat becomes a substantial challenge to the power-hungry electronics. Here, we demonstrate an interpenetrating architecture of electrocaloric polymer with highly thermally conductive pathways that achieves a 240% increase in the electrocaloric performance and a 300% enhancement in the thermal conductivity of the polymer. A scaled-up version of the device prototype for a single heat spot cooling of 5 G chip is fabricated utilizing this electrocaloric composite and electromagnetic actuation. The continuous three-dimensional (3-D) thermal conductive network embedded in the polymer acts as nucleation sites of the ordered dipoles under applied electric field, efficiently collects thermal energy at the hot-spots arising from field-driven dipolar entropy change, and opens up the high-speed conduction path of phonons. The synergy of two components, thus, tackles the challenge of sluggish heat dissipation of the electroactive polymers and their contact interfaces with low thermal conductivity, and more importantly, significantly reduces the electric energy for switching the dipolar states during the electrocaloric cycles, and increases the manipulable entropy at the low fields. Such a feasible solution is inevitable to the precisely fixed-point thermal management of next-generation smart microelectronic devices. Efficient thermal structure and precise heat management become a substantial challenge for electronics. Here, authors utilize the synergistic effect of classic heat transfer and electrocaloric cooling for fixed-point thermal management of chips. [ABSTRACT FROM AUTHOR]

Electrical manipulation of spins is essential to design state-of-the-art spintronic devices and commonly relies on the spin current injected from a second heavy-metal material. The fact that chiral antiferromagnets produce spin current inspires us to explore the magnetization switching of chiral spins using self-generated spin torque. Here, we demonstrate the electric switching of noncollinear antiferromagnetic state in Mn3Sn by observing a crossover from conventional spin-orbit torque to the self-generated spin torque when increasing the MgO thickness in Ta/MgO/Mn3Sn polycrystalline films. The spin current injection from the Ta layer can be controlled and even blocked by varying the MgO thickness, but the switching sustains even at a large MgO thickness. Furthermore, the switching polarity reverses when the MgO thickness exceeds around 3 nm, which cannot be explained by the spin-orbit torque scenario due to spin current injection from the Ta layer. Evident current-induced switching is also observed in MgO/Mn3Sn and Ti/Mn3Sn bilayers, where external injection of spin Hall current to Mn3Sn is negligible. The inter-grain spin-transfer torque induced by spin-polarized current explains the experimental observations. Our findings provide an alternative pathway for electrical manipulation of non-collinear antiferromagnetic state without resorting to the conventional bilayer structure. Under an applied current, chiral antiferromagnets, such as Mn3Sn, can produce a spin-polarized current. Here, by varying the thickness of a buffering layer, the authors show that this spin-polarized current can drive self-induced switching in polycrystalline Mn3Sn. [ABSTRACT FROM AUTHOR]

Nanostructured Au films fabricated by the assembling of nanoparticles produced in the gas phase have shown properties suitable for neuromorphic computing applications: they are characterized by a non-linear and non-local electrical behavior, featuring switches of the electric resistance whose activation is typically triggered by an applied voltage over a certain threshold. These systems can be considered as complex networks of metallic nanojunctions where thermal effects at the nanoscale cause the continuous rearrangement of regions with low and high electrical resistance. In order to gain a deeper understanding of the electrical properties of this nano granular system, we developed a model based on a large three dimensional regular resistor network with non-linear conduction mechanisms and stochastic updates of conductances. Remarkably, by increasing enough the number of nodes in the network, the features experimentally observed in the electrical conduction properties of nanostructured gold films are qualitatively reproduced in the dynamical behavior of the system. In the activated non-linear conduction regime, our model reproduces also the growing trend, as a function of the subsystem size, of quantities like Mutual and Integrated Information, which have been extracted from the experimental resistance series data via an information theoretic analysis. This indicates that nanostructured Au films (and our model) possess a certain degree of activated interconnection among different areas which, in principle, could be exploited for neuromorphic computing applications. [ABSTRACT FROM AUTHOR]

The recent progress in sequencing technology allowed the compilation of gene lists for a large number of organisms, though many of these organisms are hardly experimentally tractable when compared with well-established model organisms. One popular approach to further characterize genes identified in a poorly tractable organism is to express these genes in a model organism, and then ask what the protein does in this system or if the gene is capable of replacing the homologous endogenous one when the latter is mutated. While this is a valid approach for certain questions, I argue that the results of such experiments are frequently wrongly interpreted. If, for example, a gene from a parasitic nematode is capable of replacing its homologous gene in the model nematode Caenorhabditis elegans, it is often concluded that the gene is most likely involved in the same biological process in its own organism as the C. elegans gene is in C. elegans. This conclusion is not valid. All this experiment tells us is that the chemical properties of the parasite protein are similar enough to the ones of the C. elegans protein that it can perform the function of the C. elegans protein in C. elegans. Here I discuss this misconception and illustrate it using the analog of similar electric switches (components) controlling various devices (processes). [ABSTRACT FROM AUTHOR]

In this work, a series compositions of [(0.95−x)(Bi0.5Na0.3K0.2)TiO3–xSrTiO3–0.05(Ba0.8Ca0.2) TiO3] Pb-free ceramics (0.0 ≤ x ≤ 0.2) abbreviation (BKNT–ST–BCT) were synthesized by conventional sintering method. Effect of ST addition on the crystal structure, domain structure, dielectric and ferroelectric properties were investigated. The crystal structure was monitored by XRD and the patterns shown phase crossover from tetragonal to pseudo-cubic caused by lower crystal symmetry of lattice effect at high content of ST. Morphology of sintered ceramics were characterized by SEM, while the domain structure of ST = 0.0 at different temperatures was examined by In situ TEM. Diffused phase transition corresponding to ferroelectric to ergodic relaxor at lower T has been observed at depolarization temperature (Td) at (ST < 0.15), while the permittivity peak which detected at ST = 0.2 in whole range of temperature denote non-ergodic relaxor to paraelectric phase transition. All compositions show normal ferroelectric (P–E) loop at room temperature even ST = 0.2 with low coercive field (Ec ~ 15 kV/cm), while slim relaxor (P–E) loop was observed at (T = 200 °C). Present normal ferroelectric properties of ST = 0.2 are attributed to the domain growth and domain wall displacement above the domain switching electric field. All samples belonging to (x ≤ 0.1) shown current peak corresponding to ferroelectric phase transition at domain switching field. Samples belonging to (x ≥ 0.15) shown two nominal peaks where the second peak is corresponding to ferroelectric-to-another ferroelectric phase transition with different crystal symmetry. [ABSTRACT FROM AUTHOR]

We report on low-temperature noise measurements of a single electron transistor (SET) immersed in superfluid 4He. The device acts as a charge sensitive electrometer able to detect the fluctuations of charged defects in close proximity to the SET. In particular, we measure telegraph switching of the electric current through the device originating from a strongly coupled individual two-level fluctuator. By embedding the device in a superfluid helium immersion cell, we are able to systematically control the thermalizing environment surrounding the SET and investigate the effect of the superfluid on the SET noise performance. We find that the presence of superfluid 4He can strongly suppress the switching rate of the defect by cooling the surrounding phonon bath. [ABSTRACT FROM AUTHOR]

Topological photonics has revolutionized our understanding of light propagation, providing a robust way to manipulate light. So far, most of studies in this field are focused on designing a static photonic structure. Developing a dynamic photonic topological platform to switch multiple topological functionalities at ultrafast speed is still a great challenge. Here we theoretically propose and experimentally demonstrate a reprogrammable plasmonic topological insulator, where the topological propagation route can be dynamically changed at nanosecond-level switching time, leading to an experimental demonstration of ultrafast multi-channel optical analog-digital converter. Due to the innovative use of electric switches to implement the programmability of plasmonic topological insulator, each unit cell can be encoded by dynamically controlling its digital plasmonic states while keeping its geometry and material parameters unchanged. Our reprogrammable topological plasmonic platform is fabricated by the printed circuit board technology, making it much more compatible with integrated photoelectric systems. Furthermore, due to its flexible programmability, many photonic topological functionalities can be integrated into this versatile topological platform. The development of fast and dynamic topological photonic platforms is an ongoing challenge. Here, the authors demonstrate a reprogrammable plasmonic topological insulator in which ultrafast electric switches allow for nanosecond-level switching time between different configurations. [ABSTRACT FROM AUTHOR]

In this work, 0.94(K0.48Na0.52)0.935Li0.065NbO3–0.06BaZrO3 (abbreviated as KNLN–0.06BZ) lead-free ceramics were prepared by conventional sintering (CS) and three-step sintering (TSS). The effects of sintering process on the microstructure and piezoelectric properties of ceramics were systematically studied. The result showed that, the ceramic prepared by TSS obtained higher density and better electrical properties compared to the ceramic prepared by CS. As we all know, the formation of defects will have a pinning effect on the domain switching. According to the results of impedance spectroscopy analysis, the ceramics prepared by TSS have fewer oxygen vacancies, which will make domain switching easier at an applied electric field, resulting in more excellent piezoelectric activity. The ceramics prepared by TSS with different sintering conditions showed different properties, but multiple phases may coexist in all ceramic samples according to the analysis of XRD, and the domain can adequately switch at an external electric field due to lower energy barrier at the phase boundary, resulting in high piezoelectric properties of ceramics. Hence, when the sintering condition was 1050 °C/0 min–1150 °C/5 min–1070 °C/20 h, the ceramic samples exhibited an optimal performance of ρ = 4.51 g/cm3, d33 ~ 258 pC/N, kp ~ 0.35, and TC ~ 328 ºC. This superior result manifests that the KNLN–0.06BZ ceramic prepared by TSS is a promising ceramic for industrial application. [ABSTRACT FROM AUTHOR]

In this paper, (Pb0.98La0.02) (ZrxSn1-x)0.995 O3 (PLZS) antiferroelectric materials with different Zr/Sn ratios were fabricated by means of the rolling process, and the effects of Zr/Sn ratio on the phase structure and dielectric properties were systemically studied. All samples exhibited an orthorhombic structure. Furthermore, the results showed that the ABO3 phase structure could be easily formed when the Zr/Sn ratio was close to 1:1. The saturation polarization strength and the energy storage density increased with increasing Zr content, reaching peak value of 36 μC/cm2 and 9.5 J/cm3 at 0.49 and 0.55, respectively, and then decreased with a further increase of the Zr content. Besides, with increasing Zr content, the energy storage efficiency initially maintained a stable value of ~ 90% and then gradually decreased. The switching electric field of these materials was around 30 kV/mm and increased slightly with increasing Zr content. For all these samples, the dependence of dielectric constant on temperature varied similarly. A new intermediate state named "multicell cubic" appeared during the phase transition from the antiferroelectric phase to the paraelectric phase, which was different from the phase transition of traditional antiferroelectric materials. Moreover, the Curie temperature increased with increasing Zr content and then decreased. Based on the above result, PLZS AFEs could be a promising high-power energy storage material. [ABSTRACT FROM AUTHOR]

The paper presents the first results of an exploratory research work, aiming the experimental evaluation of the mechanical contact between conforming surfaces of metallic bodies. The proposed procedure—that is based on the measurement of electric potentials—is able to determine the actual contact pattern and estimate the force distribution on the opposing surfaces. In the present paper, the contact properties along a curve are evaluated, but the basic principles supporting the solution of the more general surface contact problem are also laid down. The goal of this research work is to provide a reliable basis for the investigation of contact-related effects on the modal properties of structures and machines. The distribution of electric contact resistivity can also be assessed using this method, opening the way to the refined characterization of electric switches and connectors. During the application of the method, measured electric voltage values are processed by a neural network trained on a data set generated by finite element software. The resulting electric contact conductivity distribution is used to determine the contact force distribution, taking into account the equilibrium of forces and moments. The results are also checked by available alternative experimental methods. [ABSTRACT FROM AUTHOR]

We consider radio-frequency ion guides formed by electrodes, which are periodic sequences of circular apertures. With the help of pulse voltages arranged as trains of a special type, a relay-switched sequence of axial distributions of the pseudopotential can be organized along the axis of the system in the form of space waves with alternating maxima and minima, which convey charged particles along the conveying channel. The disadvantage of the proposed conveying technology is the obligatory presence of neutral gas in moderate amounts, which dampens the excess kinetic energy acquired by charged particles in the jump-like switching of the radio-frequency electric field. An advantage of the proposed conveying technology is the simplified form of radio-frequency voltages applied to the electrodes of the device and the flexible control of the guiding velocity in Gas Chromatography–Mass Spectrometry interfaces, for example. [ABSTRACT FROM AUTHOR]

Smog pollution deteriorates environmental quality and has severe health risks. This affects the daily lives of people in China, particularly in urban areas. Along with other factors, a large portion for smog comes from transportations, making it dense and more hazardous in urban areas. The Chinese government aims to reduce air pollution by promoting electric vehicles and green modes for mobility along with other environmental protection measures. The study explores the switching intentions of people from motorized vehicles to electric vehicles by integrating push-pull-mooring model and institutional theory. The study incorporates environmental quality, regulative environment, alternative attractiveness, normative environment, self-(decision)efficacy, and willingness to pay into an integrated framework. The study further analyzes the green behavior of consumers by extending switching intentions for electric vehicles. The integrated framework explains mooring as the most influential factor followed by normative environment from pull factors and environmental quality from push factors. The effect of regulative environment remains weak and significant, but the effect of alternative attractiveness remains weak and insignificant. The switching intentions strongly and significantly explain green behavior. Furthermore, mooring moderates the relationship between push factors, some of the pull factors, and switching intentions. [ABSTRACT FROM AUTHOR]

We demonstrate a technique to generate new class of exact solutions to the Einstein-Maxwell system describing a static spherically symmetric relativistic star with anisotropic matter distribution. An interesting feature of the new class of solutions is that one can easily switch off the electric and/or anisotropic effects in this formulation. Consequently, we show that a plethora of well known stellar solutions can be identified as sub-class of our class of solutions. We demonstrate that it is possible to express our class of solutions in a simple closed form so as to examine its physical viability for the studies of relativistic compact stars. [ABSTRACT FROM AUTHOR]

Pb0.99Nb0.02(Zr0.85Sn0.13Ti0.02)0.98O3-x mol% La (PNZST-xLa, x = 0, 0.005, 0.01, and 0.02) antiferroelectric ceramics with orthorhombic perovskite structure were synthesized by solid-state reaction methods and the effect of La content on the phase stability and energy storage properties of PNZST-xLa was investigated. The introduction of La can enhance the stability of antiferroelectric phase and broaden the dielectric peak. Moreover, La doping leads to an increase of grain boundary resistance. La-doped PNZST ceramics show larger recoverable energy density and higher energy efficiency than un-doped PNZST ceramic due to the increased switching electric field and polarization as the La doping. Meanwhile, the temperature- and electric field-dependent energy storage properties were studied. The energy storage density increases with increasing electric field but declines with increasing temperature. [ABSTRACT FROM AUTHOR]

Tungsten disulfide (WS2) quantum dots (QDs) embedded in polyvinylpyrrolidone (PVP) based flexible memristive devices were prepared, and those devices exhibited typical bistable electrical switching and remarkable nonvolatile memristive behaviors. Maximum electricity ON/OFF ratio obtained from the current–voltage (I-V) curves of the device is close to 104. The set voltage of the device is +0.7 V, which effectively reduced the energy consumption. The retention times extracted from data for the devices were as large as 1 × 104 s, which points to these devices having nonvolatile characteristics. Moreover, the highly flexible characteristics of the devices were demonstrated by bending the devices. The carrier transport mechanisms were explained by fitting the I-V curves, and possible operating mechanisms of the devices can be described based on the electron trapping and detrapping processes. WS2 QDs uniformly dispersed in pure transparent N, N-Dimethylformamide (DMF) were obtained by using ultrasonication and a hydrothermal process in this work. [ABSTRACT FROM AUTHOR]

We consider the stabilization problem for an electrodynamic tether system (EDTS) in a circular near-Earth orbit in the position where the tether is stretched along the local vertical. To solve this problem, we propose an original EDTS design scheme that includes a negatively charged collector at the lower end of the tether and a positively charged collector at the upper end of the tether. The magnitude of the charge on the negatively charged collector is controlled by electronic emitters. We show both analytically and numerically that the Lorentz force moment acting on the EDTS due to charged collectors at the ends of the tether significantly expands the stability area for the vertical position of the tether. In addition, controlling the charge on the negatively charged collector according to the current angular motion of the tether allows to create a control component of the Lorentz torque that has dissipative nature. The simultaneous operation of restoring and dissipative-like components of the control Lorentz torque allows us to ensure the asymptotic stability of the vertical position of the tether without having to switch off the electric current flowing along the tether. The proposed control method can be used to stabilize the EDTS in order to increase the efficiency of its operation on the removal of space debris. [ABSTRACT FROM AUTHOR]

In recent years, the biosynthesis of nanoparticles is gaining much importance as it uses non-toxic chemicals and thereby, reduces environmental hazards. The bio-synthesized nanoparticles finds application in various biomedical fields because of its biocompatibility. Natural biomaterials and biopolymers have excellent physiochemical properties to reduce bulk materials into nanoparticles. Bombyx mori silk fibroin is such a natural biopolymer and is used as a bio-template to produce silver nanoparticles (AgNPs). Silver nitrate is added to the prepared silk fibroin (SF) solution at different combinations to obtain the AgNPs. The SF–AgNPs colloidal solution is used to prepare free standing biopolymer–nanocomposite (SF–AgNPs BNCs) films. The prepared SF–AgNPs BNCs were characterized with XRD, FT-IR, SEM, DSC, and TGA–DTG to study its physical properties and application, AC conductivity, and dielectric properties. It was observed that AgNPs changed the structural, thermal, dielectric, and AC conductivity of the SF films. The SF films possess good conductivity with the presence of AgNPs, hence can be used in bio-sensor and implantable thermo electric wireless switching applications. [ABSTRACT FROM AUTHOR]

Molecular switches on solid surfaces raise an important issue in digital electronic devices. It has been frequently tried to design devices to perform basic functions at the molecular scale. In this paper, the Perdew-Burke-Ernzerhof (PBE) and PBE+van der Waals (vdW) were utilized in the framework of density functional theory (DFT) to model CO optimization on a graphene surface. Among the different external stimuli, electric fields serving as a useful probe were used to activate CO switching properties. The molecular conformation of CO, total dipole orientation, and charge transfer orientation were manipulated by turning an external electric field ON and OFF. The molecular conformation switched from a parallel orientation in a negative electric field towards a perpendicular orientation in a positive electric field. The total dipole moment switched from − 8.56 Debye (D) in an electric field of − 1.0 V/Å to 3.64 D in an electric field of + 1.0 V/Å. Charge transfer was seen to switch with the electric field switching. In the negative electric field, the charges were transferred from graphene to CO, while a reverse transfer occurred in the positive electric field. In addition, it was shown that CO desorption occurred in an electric field of greater than ± 1.0 V/Å. Eventually, the ON-to-OFF state transition was accompanied by switching between the positive and negative dipole moments, adsorption and desorption states, and positive and negative charge transfers when the external field direction and intensity were switched. [ABSTRACT FROM AUTHOR]

The mechanism of relaxation of the electric polarization in thin films of rare-earth-doped bismuth iron garnet on glass and gallium gadolinium garnet substrates is determined in magnetic fields of 0 and 12 kOe in the temperature range of 80–380 K. The change in the sign of the residual electric polarization after switching off the electric field and the magnetic-field-induced shift of the hysteresis loop in the applied magnetic field are found. Linear and quadratic magnetoelectric effects with the tensor components depending on the substrate type are observed. The linear magnetoelectric effect is related to the spin–orbit coupling of electrons at the film–substrate interface, whereas the quadratic one is determined by the exchange–striction mechanism. [ABSTRACT FROM AUTHOR]

This paper presents the design, fabrication and characterization of capacitive type MEMS switch for space and terrestrial communication applications. The deviation in measured actuation voltage and RF response of the switches are discussed in terms of the process variation which occurred unintentionally during the fabrication of devices. For example the measured actuation voltage is 15 V, about 20% higher than the designed voltage of 12.25 V. The deviation corresponds to the increase in thickness of the membrane while electroplating. The impact of process parameters on mechanical resonance frequency of the switches, and on/off time is also discussed. Measured S-parameters shows isolation of > − 20 dB for 7-16 GHz and an insertion loss better than − 0.6 dB up to 20 GHz. The capacitance ratio of the fabricated switch is 77, which is 15% lower than the designed capacitance ratio. The switch has been tested for 1 million 65 thousand cycles without switching failure. The deviation of simulated and measured results is discussed in the following sections. [ABSTRACT FROM AUTHOR]

We report on the design, fabrication, and demonstration of the operation of a latching (nonvolatile) low-loss microwave switch at 4.2 K and 40 mK using the phase-change material germanium telluride (GeTe) as the switching element. The single-pole double-throw (SPDT) series-shunt switch has a single RF input and two selectable RF outputs. An insertion loss of less than 1 dB from DC to 10 GHz was demonstrated, with virtually identical performance across 5000 switching cycles at 40 mK. We have also characterized the resistance of the GeTe thin-film material used in the fabrication of the SPDT switch from room temperature down to 11 mK. While bulk GeTe is known to become superconducting below 1 K, these GeTe films showed no detectable superconducting transition, resulting in a switch with finite on-state DC resistance. Given the wide range of phase-change material candidates reported in the literature and prior evidence of superconductivity, this demonstration paves the way for future development of a near-ideal switch which could have zero on-state DC resistance at cryogenic temperatures. [ABSTRACT FROM AUTHOR]

A MEMS inertial switch with electrostatic force assistance and multi-step pulling action has been designed, fabricated and tested. The new design can help the electrodes weaken the bounce and keep a long contact before the leakage of electricity ends. Compared with the traditional inertial switch, the designed flexible connecting multi-plane moving electrode can realize the multi-step pulling action to reduce the pulling voltage and eliminate the rebounding phenomenon. The fixed electrode is designed as an array-type interconnection structure, which is fixed on the insulated glass substrate and mutually insulated with the pulling electrode by air. The dynamic switching and pulling performance under different boundary conditions are simulated by the COMSOL multi-physics field coupling commercial software, which confirms the designed inertial switch realize the expected functions. The fabricated inertial switch is tested by a standard dropping hammer system, which shows that the inertial switch with electrostatic force assistance has no bounce behavior, and ~ 540 μs long stable contact time is obtained. [ABSTRACT FROM AUTHOR]

This study presents a novel step-up switched capacitor multilevel inverter (SCMLI) structure. The proposed structure comprises 2 unequal DC voltage sources, 4 capacitors, and 14 unidirectional power switches. It can synthesize 21 output voltage levels. The important features of the proposed topology are its self-voltage boosting and inherent capacitor voltage balancing capabilities. Furthermore, a cascaded structure of the proposed SCMLI with an asymmetric DC voltage source configuration is presented. The proposed topology and its cascaded structure are compared with conventional and other recently developed topologies in terms of different aspects, such as the required components to produce a specific number of output voltage levels, the total standing voltage (TSV) and peak inverse voltage of the structure, and the maximum number of switches in the conducting path. Furthermore, a cost function is developed to verify the cost-effectiveness of the proposed topology with respect to other topologies. The TSV of the proposed topology is significantly lower than those of other topologies. Moreover, the developed topology is cost-effective compared with other topologies. A detailed operating principle, power loss analysis, and selection procedure for switched capacitors are presented for the proposed SCMLI structure. Extensive simulation and experimental studies of a 21-level inverter structure prove the effectiveness and merits of the proposed SCMLI. [ABSTRACT FROM AUTHOR]

In this paper a new generalized space vector pulse width modulation scheme is proposed based on the principle of reverse mapping to drive the switches of multilevel inverters. This projected scheme is developed based on the middle vector of the subhexagon which holds the tip of the reference vector, which plays a major role in mapping the reference vector. A new approach is offered to produce middle vector of the subhexagon which holds tip of the reference vector in the multilevel space vector plane. By using middle vector of the subhexagon, reference vector is linked towards the inner two level sub-hexagon. Then switching vectors, switching sequence and dwell times corresponding to a particular sector of a two-level inverter are determined. After that, by using the two level stage findings, the switching vectors related to exact position of the reference vector are directly generated based on principle of the reverse mapping approach and do not need to be found at n level stage. In the reverse mapping principle, the middle vector of subhexagon is added to the formerly found two level switching vectors. The proposed generalized algorithm is efficient and it can be applied to an inverter of any level. In this paper, the proposed scheme is explained for a five-level inverter and the performance is analyzed for five level and three level inverters through MATLAB. The simulation results are validated by implementing the propose scheme on a V/f controlled three-level inverter fed induction motor using dSPACE control desk. [ABSTRACT FROM AUTHOR]

A novel passive lossless soft-switching single inductor dual buck full-bridge inverter (PLSSIDBFBI) is presented in this paper. To accomplish this, a passive lossless snubber circuit is added to a dual buck full-bridge inverter. Therefore, the advantages of the dual buck full-bridge inverter are included in the proposed inverter, and the inverter has just one filter inductor, which can decrease the system volume and improve the integration. In addition, the passive lossless snubber circuit achieves soft-switching by its own resonance, and all of the energy stored in the passive lossless snubber circuit can be transferred to load. A comparison between eight topologies is performed in this paper, and the analysis shows that the proposed soft-switching inverter topology has high reliability and efficiency. Finally, experimental results obtained with a 1 kW prototype verify the theoretical analysis and demonstrate the prominent characteristics of a reduced switching loss and improved efficiency. [ABSTRACT FROM AUTHOR]

A novel active controlled primary current cutting-off zero-voltage and zero-current switching (ZVZCS) PWM three-level dc-dc converter (TLC) is proposed in this paper. The proposed converter has some attractive advantages. The OFF voltage on the primary switches is only Vin/2 due to the series connected structure. The leading-leg switches can obtain zero-voltage switching (ZVS), and the lagging-leg switches can achieve zero-current switching (ZCS) in a wide load range. Two MOSFETs, referred to as cutting-off MOSFETs, with an ultra-low on-state resistance are used as active controlled primary current cutting-off components, and the added conduction loss can be neglected. The added MOSFETs are switched ON and OFF with ZCS that is irrelevant to the load current. Thus, the auxiliary switching loss can be significantly minimized. In addition, these MOSFETs are not series connected in the circuit loop of the dc input bus bar and the primary switches, which results in a low parasitic inductance. The operation principle and some relevant analyses are provided, and a 6-kW laboratory prototype is built to verify the proposed converter. [ABSTRACT FROM AUTHOR]

We present the results of studying a cascade microwave switch capable of stable operation at the power level of a regular waveguide. The cascade stage is formed by connecting several identical H-joints in the side branch of the tee of a conventional microwave interference switch. The connection distributes the power of the switched wave between the joints and varies the level of the switched power. The method of the scattering matrix is used to analyze the properties of such a switch based on H-joints with different matching levels of the side branch. It is shown that the cascade of sufficiently well-matched joints can decrease the level of the switched power by several times and ensure a higher operating power and a better stability of the switching, while the cascade with coupling worse than a certain boundary value can increase the power of the switched mode by several times and ensure switching of a lower-power mode. The numerical criterion of the coupling quality is found, which divides operation of the switch with increased and decreased switched powers. It is also found that in the switch under consideration, the microwave energy is distributed between the cascade elements in the process of the switching, which can affect greatly both the switching process and the characteristics of the switched mode during the process. The results of the analysis are compared with the experimental data at high and low power levels. [ABSTRACT FROM AUTHOR]

This paper presents design and simulation of uniform structured RF MEMS capacitive shunt switch using FEM tool and HFSS software. The switches with different shaped meanders and perforations which result in less spring constant, less pull-in voltage, high isolation loss, high switching speed and low insertion loss have been designed. From the simulated results it is observed that the rectangular perforations gives the better results, when compared with square and cylindrical shaped perforations. Comparative study is done for zigzag, plus and three square shaped meander along with rectangular perforations on each structure. When the gap between the dielectric and the movable beam is 0.8 µm, the up state capacitance for HfO2 is 4.06fF and for Si3N4 is 3.80fF. The downstate capacitance for HfO2, Si3N4 is 49fF, 26.9fF respectively. The capacitance ratio is 120.6. Poly-tetra-fluoro-ethylene material is given for the movable beam whose young’s modulus is 0.4 GPa and the spring constant is calculated theoretically for each structure; by using this the pull in voltage and the settling time are calculated. Step switch with three square Meander has switching time 10.25 µs, pull in voltage as 2.45 V. By using HFSS 3-D electromagnetic model we observed the return loss (S11) is less than −60 dB, the insertion loss is less than −0.07 dB in the range of 1–40 GHz frequency and switch isolation (S21) is −61 dB at 28 GHz frequency. [ABSTRACT FROM AUTHOR]

Simulation results are compared with experimental data to define the integral breakdown criterion for the spark gaps of the switches of the LTDs with oil insulation and to determine the influence of the inductance of the trigger inductor on the delay of the switch firing. The results confirm that the shape of the output square pulse produced by the oil-insulated LTDs can be corrected as required if the trigger inductors are used to trigger the cavity switches. [ABSTRACT FROM AUTHOR]

The features of the electromagnetic modeling of a microwave switch for the frequency range of 1-20 GHz, which is then produced by CMOSHFET technology on AlGaN/GaN heterostructures using high-K dielectrics and contacts with capacitive coupling, are considered. [ABSTRACT FROM AUTHOR]

A change in the character of the electric switching of polydomain ferroelectric-ferroelastic gadolinium molybdate in an external magnetic field has been detected. This change has been attributed to a magnetically stimulated increase in the pinning of domain walls. Under certain conditions, the loop of switchable polarization is degenerated into an ellipse characteristic of a linear insulator with leakage current. [ABSTRACT FROM AUTHOR]

Micro electromechanical system (MEMS) shunt capacitive switches behave chiefly as a capacitor at both up and down states. Therefore, input-output matching for these switches is affected by varying the frequency. Although increasing the amount of capacitance at the up state reduces the actuation voltage, it deteriorates the RF parameters. This paper proposes a remedy for this problem in the form of two short high-impedance transmission lines (SHITLs) which are included at both ends of the MEMS switch. The SHITLs are implemented through adoption of a discontinued CPW transmission line. With this implementation, the switch can be modelled as a T circuit, neutralizing a capacitance behavior of MEMS switch at the up state. The paper also proposes an optimised fabrication process to realize a flat and planar bridge for the suggested RF MEMS switch. The measurement recorded by SEM and AFM shows that the proposed method significantly improves the planarity of the membrane. The RF and mechanical parameters of the fabricated switch are evaluated by Vector Network Analyser and Laser Doppler Vibrometer. At the up state, the switch has a return loss less than −20 dB in the entire frequency band (C-K). The isolation at the down state is better than 10 dB for the lower frequencies and increases to values better than 18 dB for the higher frequencies. The measured pull-in voltage is almost 20 V and the mechanical resonance frequency is 164 kHz. [ABSTRACT FROM AUTHOR]

This paper presents a high-side switch driver IC capable of improving the current sensing accuracy and providing reverse battery protection. Power semiconductor switches used to replace relay switches are encumbered by two disadvantages: they are prone to current sensing errors and they require additional external protection circuits for reverse battery protection. The proposed IC integrates a gate driver and current sensing blocks, thus compensating for these two disadvantages with a single IC. A p-sub-based 90-V 0.13-µm bipolar-CMOS-DMOS (BCD) process is used for the design and fabrication of the proposed IC. The current sensing accuracy (error ≤ ±5% in the range of 0.1 A-6.5 A) and the reverse battery protection features of the proposed IC were experimentally tested and verified. [ABSTRACT FROM AUTHOR]

This paper investigates the stability of a class of variable-time switched systems whose switching times are dependent on system states. To overcome the difficulty that switching times are not explicit, we construct a new fixed-time switched impulsive system whose stability is equivalent to the stability of the variable-time switched system. In the light of the mode-dependent average dwell time and the constructed fixed-time switched impulsive systems, sufficient conditions for exponential stability of variable-time switched systems are obtained. Finally, two applications are employed to indicate the effectiveness of the proposed results. [ABSTRACT FROM AUTHOR]

Multilevel converters have attracted a lot of attention in recent years. The efficiency parameters of a multilevel converter such as the switching losses and total harmonic distortion (THD) mainly depend on the modulation strategy used to control the converter. Among all of the modulation techniques, the selective harmonic elimination (SHE) method is particularly suitable for high-power applications due to its low switching frequency and high quality output voltage. This paper proposes a new expression for the SHE problem in five-level converters. Based on this new expression, a simple analytical method is introduced to determine the feasible modulation index intervals and to calculate the exact value of the switching angles. For each selected harmonic, this method presents three-level or five-level waveforms according to the value of the modulation index. Furthermore, a flowchart is proposed for the real-time implementation of this analytical method, which can be performed by a simple processor and without the need of any lookup table. The performance of the proposed algorithm is evaluated with several simulation and experimental results for a single phase five-level diode-clamped inverter. [ABSTRACT FROM AUTHOR]

Design and fabrication of a folded leg Ka-band RF micro electro mechanical systems (RF MEMS) is presented. The mechanical design is carried out to observe minimum permanent deformation on the MEMS bridge after our in-house MEMS packaging process temperature treatment (200 °C). On the other hand, the actuation voltage is aimed as <30 V and measured as 24-25 V before thermal treatment. Moreover, the switch shows 28-29 V actuation voltage after thermal treatment. The fabricated switch shows −0.4 dB insertion loss for the up state position at Ka-band, before and after heat treatment. The switch is fabricated on quartz wafer using an in-house surface micromachining process with a new amorphous silicon sacrificial layer structure. [ABSTRACT FROM AUTHOR]

This Paper focuses on improving the Harmonic Rejection Ratio (HRR) and the linearity of 3-Path 8-Phase harmonic rejection mixer with modified transconductance stage. The mixer core incorporates a feed-forward compensation technique in the transconductance stage for improving the linearity of the mixer with an Third order Input Intercept Point (IIP3) of 14 dBm. The Harmonic Rejection Mixer (HRM) using mixer cores with modified transconductance stage was designed using 90 nm CMOS process technology and the simulation results shows an improvement of IIP3 point of more than 25 dBm. A conversion gain of 12-4 dB was observed over the frequency range of 2.26-2.8 GHz (540 MHz bandwidth). Maximum third order HRR ( $$HRR_3$$ ) of 45 dB and fifth order HRR ( $$HRR_5$$ ) of 55 dB was observed on sweeping the RF power from −30 to 10 dBm. Deviations on the performance of the HRM was found to be very minimal on PVT variation. [ABSTRACT FROM AUTHOR]