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Pulsed electric field disinfection is an effective non-thermal water disinfection technology. Compared to conventional disinfection techniques, PEF inactivation has several advantages including no by-products. In this context, the use of silver ions in conjunction with a reverse osmosis filtration system has been proposed as a safe and cost-effective treatment approach that can be used in a point of use technologies. This system contains two silver meshes as electrodes inside a reverse osmosis membrane with the application of a pulsed electric field on it as a disinfection method, After conducting chemical and physical tests of the water samples before and after the treatment system, it was noticed that most of these characteristics were significantly affected by increasing the number of electrical impulses and the intensity of the applied voltage as a result of the increase in the ionization process of silver in water.

One of the major challenges of the food industry is to develop more sustainable processing technologies. To address this change, it is necessary to have more information about available innovative technologies and their effect on different food matrices and processes to ensure efficiency in food chain management. The aim of this research was to increase the understanding of the physical modifications induced by the combination of pulsed electric field (PEF) pre-treatment and further drying in carrot and potato tissues by modelling the sorption isotherms and the textural properties. High coefficient of determination up to 0.980 for GAB and 0.977 for BET were obtained confirming the good ability of both models to describe the sorption isotherm of foodstuff. Either BET and GAB classified carrot in a III type shape and potato in II type shape for sorption isotherm. Mechanical properties for carrot and potato considering all PEF treatment and aw levels were reported and fitted by modified Fermi distribution. High coefficient of determination up to 0.995 confirm the ability of Fermi model to describe mechanical properties in relation to water activity (aw).

As a three-dimensional characterization method, atom probe tomography can provide key information that other methods cannot offer. Conductive coatings have proved to be an effective way for biological samples, and nonconductive samples in general, to be analyzed using voltage-pulsed atom probe tomography. In this study, we analyzed the effects of graphene coating on an electrically conductive material and were able to confirm the detection of carbon atoms. We compare quantitative electrostatic field metrics for a single-coated and a multi-coated specimen and measure both a reduced voltage after graphene coating and lowered charge-state ratios for different ion species, suggesting a lowered evaporation field related to the graphene coating. This information will be instructive for future studies on graphene-coated, nonconductive biological specimens.

A 320 x 240 indirect time-of-flight (i-ToF) image sensor with a 5.6-μm two-tap 1.5-V pump gate modulation pixel has been designed. Novel characteristics, such as the optimized pinned layer doping and potential buffer region (PBR) structure with pump gate modulator (PGM), are proposed to achieve a maximum lateral modulation electric field of 1500 V/cm under the front-side illumination (FSI) process. As a result, the proposed time-of-flight (ToF) sensor shows 200-mW power consumption and 54% demodulation contrast (DC) at 50-MHz modulation frequency, depth noise less than 1% with 940-nm illuminator from 0.3 to 3 m.

The degradations of electrical parameters for depletion mode GaN devices in the cascode configuration under repetitive hard-switching stress are investigated in detail. With the help of TCAD simulations and comprehensive experimental analysis, two different mechanisms behind the degradations are demonstrated. Under a relatively low Vds hard-switching condition, hot electron injection is proved to be the only influence factor, which results in the increase of Rdson under low gate bias voltage. Furthermore, under the low Vds switching condition, influence of different stages on the degradation trend of the device is verified. It is found that the turn-on procedure has a greater degradation risk due to higher energy consumption. However, when Vds is high during hard-switching, the surface trapping effect is triggered due to high electric field at the end of gate field plate, and finally results in the device degradation trend. It results in the increase of the Rdson under high gate bias condition. Therefore, considering the stability and safety of power systems which adopt cascode devices as switches, shorter turn-on time or a soft-switching operation condition should be considered in the design.

ABSTRCT Sustainable light energy from ambient environment has attracted particular attention to meet the ever-growing need of small-scale electronics. The modulation of intercorrelated thermal and electronic transport is one of the crucial aspects for reliable photothermoelectric electronics. Herein, a defect-promoted photothermoelectric effect is demonstrated in densely aligned ZnO nanorod array with rich lattice defects. The defect-rich ZnO device delivers high electrical conductivity and large Seebeck coefficient to enable significant improvement of photothermoelectric energy conversion and self-powered photodetection. The position sensitivity reaches approximately 0.19 mV·mm-1, and the temperature gradient induced electric field makes up for the suppression in the photothermoelectric process. The synergism between intrinsic defects and extra temperature field plays an important role in promoting the photothermoelectric properties of dense ZnO nanorod array. This study is interesting for interpreting the thermo-phototronic phenomena as well as demonstrating the possibility of defect engineering and phonon engineering to enable highly efficient light energy scavenging and self-powered photodetection.

Insulators are the most crucial part of power systems. The insulation performance of insulators is vital for the sustainability of power systems. Recently, silicone rubber (SiR) insulators are used frequently in all sections of the power systems. In this paper, a SiR insulator currently used in power transmission systems has been analyzed under combined AC-DC voltage using the finite element method. In the analysis, positive and negative DC voltages in different amplitude ratios were superimposed over the phase-earth operating voltage of the insulator. Analyses in the study were made in time-dependent. Only DC voltage was applied to the insulator for the first 60 s, AC + DC voltage was applied between 60 to 120 s. Thus, the electric field behavior of the SiR insulator under combined AC-DC voltage has been obtained. The change of electric field based on positive and negative DC components was investigated. As a result of the study, the effect of the polarity of the DC component in the combined voltage was observed. As a result, effect of the polarity of the DC component in the combined voltage on the maximum electric field intensity was observed. (C) 2021 The Author(s). Published by Elsevier Ltd.

The present work exhibits a novel design of surface plasmon resonance (SPR) biosensor, which comprises CaF2 prism, TiO2, metal (Ag/Au), PtSe2, 2D materials (graphene/ transition metal dichalcogenides (MoS2/WS2)) and sensing medium, for point-of-care detection of various stages of malaria diseases. The transfer matrix method (TMM) is employed to examine the angular reflectivity of the proposed structure after judiciously optimizing the layer thicknesses and layer numbers. Phase interrogation technique is utilised to validate the position of occurrence of resonance angles. Additionally, the proposed SPR structure is designed using COMSOL Multiphysics, to assay the electric field intensity and electric field enhancement factor near the edge of 2D material-sensing layer interface. Simulation upshots revealed that the use of new class of 2D materials catapult the sensor performance to a new height compared to the traditional SPR configuration. A maximum sensitivity of 240.10°/RIU, quality factor of 78.46 RIU-1 and detection accuracy of 1.99 is attained for Ag-based SPR configuration with bilayer of WS2. Sensing parameters are compared with previously reported works to prove the superiority of the present research. Moreover, the real-time and label-free detection of malaria diseases makes the suggested sensor worth to fabricate as a SPR chip with the recent nanofabrication technologies.

SUMMARYRuddlesden-Popper (RP) perovskites are two-dimensional semiconductors for high performance devices. In this work, we report a long in-plane charge carrier diffusion length in 2D RP perovskite single crystals probed by scanning photocurrent microscopy. Carrier diffusion lengths of 7~14 µm are observed when the number of PbI6-2 octahedrons between organic spacers increases from 1 to 3. By detailed light intensity and electric field-dependent photocurrent measurements, we attribute the observed long diffusion length to the dominating dissociated free carrier transport. This is further validated by time-resolved photoluminescence measurements where the decay lifetime increases in the presence of an electric field. From our experiments, we conclude that the in-plane transport in RP perovskites is efficient because of the partial free carrier generation overcoming strong excitonic effects. Our results suggest that semiconducting devices fabricated from RP perovskite single crystals can be as efficient as their 3D counterparts.

In this communication, we propose glide-symmetric double-layer spoof surface plasmon polaritons (SSPPs) structures for controlling the field confinement of SSPPs to achieve antenna beam manipulation with a large frequency-scanning angle. By changing the shape of the glide-symmetric double-layer SSPPs, we can control the electric field confinement of the SSPPs to emerge symmetric or asymmetric distribution. Hence, the proposed SSPPs structure can produce electromagnetic leakage on both sides or single side, furtherly achieving dual-beam or single-beam radiation. Two SSPPs antennas with dual beams and single beam are designed, fabricated, and measured. Both the dual-beam antenna and single-beam antenna operate from 9 GHz to 24 GHz. Within the working band, the dual-beam antenna accomplishes 134.3° (-90° to +44.3°) beam-scanning angle with the realized gain of 8.03-12.17 dBi, while the single-beam antenna achieves 119° (-77.9° to 41.1°) beam-scanning angle with 10.31-14.24 dBi realized gain. The simulated and experimental results verified the beam manipulation and large frequency-scanning angle in antenna design.

Novel back-illuminated modified uni-traveling- carrier photodiodes (MUTC-PDs) are reported to demonstrate wide bandwidth and high output power performance at D-band (110–170 GHz) regime. A comprehensive design model is employed to predict and tune the frequency response by incorporating coplanar waveguides (CPWs) with different inductive peaking effects. As a demonstration, 4.5-μm-diameter photodiodes with two types of CPWs are fabricated to exhibit different frequency response profiles. Both PDs exhibit a 3-dB bandwidth over 150 GHz and the measured frequency responses are in excellent agreement with simulations. Thanks to the proper design of the CPW electrodes, the two PDs exhibit an output power roll-off of only 4.3 dB and 4.8 dB from dc to 170 GHz, respectively, and high saturation performance is maintained over the broadband frequency range of 130–170 GHz.

Nowadays, carbon frameworks derived from natural biomaterials have attracted extensive attention for electromagnetic interference (EMI) shielding due to their renewability and affordability. However, it is critical and challenging to achieve effective regulation of shielding effectiveness (SE) as well as weaken the strong EM reflection of highly conductive biomass-based carbon materials. Herein, commercial cotton pads with oriented structure were selected as carbonaceous precursor to fabricate aligned carbon networks by pyrolysis, and the EMI SE of the samples with increased temperature of 800-1000°C can be accurately controlled in the effective range of ∼21.7-29.1, ∼27.7-37.1 and ∼32.7-43.3 dB with high reflection coefficient of >0.8 by changing the cross-angle between the electric-field direction of incident EM waves and the fiber-orientation direction due to the occurrence of opposite internal electric field. Moreover, the further construction of Salisbury absorber-liked double-layer structure could result in an ultra-low reflection coefficient of only ∼0.06 but enhanced SE variation range up to ∼38.7-49.3 dB during the adjustment of cross-angle, possibly due to the destructive interference of EM waves in the double-layer carbon networks. This work would provide a simple and effective way for constructing high-performance biomass carbon materials with adjustable EMI shielding and ultra-low reflectivity.

This paper presents the characteristics of HgCdTe mid-wavelength infrared (MWIR) electron-initiated avalanche photodiodes (e-APDs) as a function of temperature under different biases. The devices show a low dark current density of the order of ${10^{ - 7}} \text{A/cm}^2$ at 80 K when the reverse bias voltage is below 4 V, with an exponential gain above 100 at − 8 V. Low excess noise factor of around 1.2 is also demonstrated for the devices at 80 K. The dark current and gain characteristics at different temperatures are analyzed, along with the device simulation results. A varied-temperature impact ionization model for MWIR e-APD devices is adopted based on the experimental results. In addition, a significant increase of the dark current in the APD device is observed at high temperature under large reverse bias, which can be associated with the local electric field redistribution due to the accumulation of holes in the depletion region at high temperatures. The analysis presented in this work paves the way to achieve a high operating temperature (HOT) of the HgCdTe APD with further optimization.

A compact tag antenna, which has a geometrical dimension of 31.5 mm × 31.5 mm × 3.2 mm, is constructed using a stacked PILA for metal-mountable applications in the UHF RFID passband. The new antenna is formed by inserting a shorted patch into a PILA structure to create a double-layered inverted antenna, which can be viewed as a cascade of two parallel resonant tanks. An increase in electric field intensity in the antenna structure has brought in sufficient capacitance for reducing the tag resonant frequency effectively to the useful UHF RFID passband. Due to the increase in the antenna reactance, conjugate impedance matching can be easily achieved between the antenna and the microchip. Fine-tuning schemes such as stubs and slits are also incorporated with the proposed tag antenna for adjusting the operating frequency to an exact precision. Measurements show that the proposed tag antenna can achieve a read distance of 7.25 m at an EIRP power of 4 W. The resonance of the proposed tag antenna is found to be very stable and it is insensitive to changes in the backing metal platform.

The use of semiconductors to construct heterojunctions to suppress the rapid recombination of photogenerated charges and holes is considered to be an effective way to improve the efficiency of photocatalytic hydrogen evolution. Herein, cobalt sulfide (CoSx) nanoparticles are cultivated in situ in the folds of three-dimensional flower-like nickel-aluminium layered double hydroxides (NiAl-LDHs) using a facile solvothermal method. The hydrogen production rate of the binary CoSx/NiAl-LDH heterojunction reaches 3678.59 μmol/g/h, which is 83.74 and 22 times the rates of CoSx and NiAl-LDH, respectively. The unique three-dimensional structure of NiAl-LDH facilitates the growth of CoSx and shortens the transfer pathway of photogenerated electrons. More importantly, the built-in electric field formed at the interface and the S-type charge transport mechanism caused by the bending of the energy band enhance not only charge separation but also maintain the strong oxidation ability of the holes. In this study, the newly designed S-scheme heterojunction offers a new strategy for enhancing photocatalytic water splitting.

Traditional carbon materials as sulfur hosts of Li-sulfur(Li-S) cathodes have slightly physical constraint for polysulfides, due to their no-polar property. Therefore, it is necessary to further enhance the affinity between sulfur hosts and polysulfides, and relieve the shuttle effects in the Li- S batteries. Herein, we report a novel vertical 2-dimensional (2D) p-SnS/n-SnS2 heterostructure sheets which grown on the surface of rGO. The excellent electrochemical properties of SnS-SnS2@rGO as Li-S cathode are ascribed to the stronger absorption effect of metal sulphides for polysulfides and the smooth trapping-diffusion-conversion effect of p-SnS/n-SnS2 heterostructure for polysulfides. As a conductive carrier for the growth of vertical 2D p-SnS/n-SnS2 heterostructure nanosheets, rGO can protect the steadiness and enhance the cycle stability of electrode, compared with heterostructure without rGO. In addition, the built-in electric field in the 2D p-SnS/n-SnS2 heterostructure during the discharge/charge processes can effectively accelerate charge transfer, and the charge transfer mechanism in SnS-SnS2 heterostructure during cycling has been investigated. At a rate capability of 2C, the designed SnS-SnS2@rGO as Li-S cathode delivers high specific capacities of 907 mAh g−1 and 571 mAh g−1 after the first cycle and 500 cycles, respectively, which shown excellent cycling ability.

In this paper, a novel structure of the high-order-mode cavity fed sequentially rotated patch antenna array is proposed for diverse polarizations. The diverse polarizations, including right hand circular polarization(RHCP), left hand circular polarization(LHCP), -45∘ linear polarization(LP), 0∘ LP, 45∘ LP, and 90∘ LP, are achieved based on the current distribution on the patches and different electric field modes in the high-order-mode cavity by adjusting the phase and amplitude of the two orthogonal feeding ports. Furthermore, from the electric field distribution in the high-order-mode cavity with different feeding schemes, arbitrary polarizations were analyzed and obtained. An 8×8 dual-circularly polarized(dual-CP) antenna is demonstrated. Good agreement between the simulated and measured results is obtained, validating the design. The experimental results show that the impedance bandwidths(

A coupling enhanced surface plasmon resonance (SPR) sensor based on coreless fiber is proposed. Compared with the common fiber, the coreless fiber is easier to perceive the changes of the external medium environment. As one-dimensional material with superior performance, the Au nano biconical particles are used to improve the sensor performance. Based on the finite element method (FEM), the electric field enhancement effect of the coupling between the SPR of the gold film and the Localized surface plasmon resonance (LSPR) of the Au nano biconical particles on the surface of the coreless fiber is analyzed, and the experimental results show that the Au nano biconical particles can improve the sensitivity. The sensitivity of the improved Au nano biconical particle sensor is 3514 nm/RIU, which is 64% higher than that of the traditional gold film SPR sensor, and the quality factor is increased by 24%. The new sensor based on Au nano biconical particles and gold film has a good application prospect in biosensor and chemical measurement.

The charging and levitation of particles using UV irradiation in an upward electric field were investigated. Glass beads with a mass median diameter of 61 μm were used for the experiments. The particle layers formed on a glass plate were irradiated by UV light with wavelengths ranging from 240 to 400 nm. The particles in the top layer were positively charged by photoemission and levitated by the electrostatic forces. The fluxes and motions of the levitated particles were analyzed by digital processing of the images obtained with a high-speed camera. The charge of each levitated particle was determined by fitting the results calculated using the equation of motion to the experimentally obtained particle motion. The charge of the particles beginning to be levitated was determined by the force balance and thus was not affected by the UV irradiance. The positive charge of the levitated particles could be increased by continuous photoemission from the particles and decreased by the capture of photoelectrons emitted by other particles. Approximately 40% of the levitated particles descended because of the negative charge clouds formed by the photoemission from the particle layers and the levitated particles. Furthermore, in a second set of experiments, an upward electric field was applied after UV irradiation. In these experiments, the particles in the top layer were levitated after applying the electric field. These particles could be gain more excess charges than the particles for which the levitation was governed by the force balance.

In this work, we experimentally investigate the effects of electric bias on the degradation of few-layer MoS2 back-gated field-effect transistors in ambient air. The devices were fabricated using mechanically exfoliated MoS2 flakes, which were transferred to a Si/SiO2 substrate by a PDMS-based transfer. We report an accelerated electric bias-induced degradation of the devices under investigation and used optical and scanning electron microscopy (SEM) to monitor changes of the morphology of the MoS2 channel. In particular, we found a linear dependency of the degradation on the electric field between the Ti/Au source and drain contacts. In addition, we identify four regions in which morphological changes occur, of which the edges of the MoS2 channel are most affected.

Ferroelectric thin/thick films with large electrocaloric (EC) effect are critical for solid state cooling technologies. Here, large positive EC effects with two EC peaks in a broad temperature range (∼100 K) were obtained in 0.95Pb0.92La0.08(Zr0.70Ti0.30)0.98O3-0.05BiFeO3 (BFO La-codoped PZT) epitaxial thin films deposited on the (100), (110) and (111) oriented SrTiO3 (STO) substrates by a sol-gel method. The thin film deposited on the (111) oriented STO substrate exhibited a stronger EC effect (∼20.6 K at 1956 kV/cm) near room temperature. However, the thin films deposited on the (100) and (110) oriented STO substrates exhibited a stronger EC effect (∼18.8 K at 1852 kV/cm and ∼20.8 K at 1230 kV/cm, respectively) around the peak of the dielectric permittivity (Tm, ∼375 K). Particularly, as the direction of the applied electric field was switched (E La-codoped PZT epitaxial thin films are promising candidates for application in the next solid-state cooling devices.

In this work, we firstly used a new two-dimensional (2D) semiconductor material Bi2O2Se for optical-fiber SPR sensor sensitization, proposed and validated a U-shaped optical-fiber SPR sensor with Au film- Bi2O2Se Sandwich structure. The finite element simulation results illustrate that the electric field strength on the surface is 2.08 times higher than that of the pure Au film, which excites a stronger SPR phenomenon thus leading to a high sensitivity of the sensor. The effect of the Radius on the sensor performance was investigated, and the optimal structural parameters were derived to fabricate the sensing probes. The RI sensitivity of the presented sensor is 6827.41 nm/RIU, 1.98 times superior to that of the pure Au film U-shaped optical SPR sensor. The sensor is insensitive to temperature fluctuations and has good repetitive and environmental stability. The proposed sensor has good potential for future applications in biomass detection, which also indicates that Bi2O2Se has good prospects for future applications in optoelectronic devices.

In this paper, for the first time, we explained a detailed physical insight for Negative Differential Resistance (NDR) to Positive Differential Resistance (PDR) transition in a ferroelectric-based negative capacitance (NC) FET and also its dependence on the device terminal voltages. Using extensive well-calibrated TCAD simulations, we have investigated this phenomenon on FDSOI NCFET. The NDR to PDR transition occurs due to Ferroelectric (FE) layer capacitance changes from a negative to positive state during channel pinch-off. This, in turn, results in a valley point in the output characteristic (IDS-VDS) at which the output resistance is infinite. We also found that we could alter the valley point location by modulating the vertical Electric field through the FE layer in the channel pinch-off region using body bias (VBB). The interface oxide charges also impacted the NDR to PDR transition, and a positive interface charge results in faster NDR to PDR transition. Further, we have utilized the modulation in NDR to PDR transition due to VBB for designing a current mirror. Results show that the output current (IOUT) variation due to VDS, reduces from ~8% to ~2% with VBB. We have also designed a single-stage common source (CS) amplifier and provided design guidelines to achieve a higher gain in the NDR region. The results obtained using a small-signal model of the FDSOI-NCFET demonstrate that ~25% higher gain can be achieved with the discussed design guidelines in the NDR region compared to the transition region of IDS-VDS. We have also explored the device scaling effect on the amplifier gain and found that ~2.23x gain can be increased with smaller channel length and higher device width.

The ferroelectric material In2Se3 is currently of significant interest due to its built-in polarisation characteristics that can significantly modulate its electronic properties. Here we employ density functional theory to determine the transport characteristics at the metal-semiconductor interface of the two-dimensional multiferroic In2Se3/Fe3GeTe2 heterojunction. We show a significant tuning of the Schottky barrier height as a result of the change in the intrinsic polarisation state of In2Se3: the switching in the electric polarization of In2Se3 results in the switching of the nature of the Schottky barrier, from being n-type to p-type, and is accompanied by a change in the spin polarization of the electrons. This switchable Schottky barrier structure can form an essential component in a two-dimensional field effect transistor that can be operated by switching the ferroelectric polarization, rather than by the application of strain or electric field. The band structure and density of state calculations show that Fe3GeTe2 lends its magnetic and metallic characteristics to the In2Se3 layer, making the In2Se3/Fe3GeTe2 heterojunction a potentially viable multiferroic candidate in nanoelectronic devices like field-effect transistors. Moreover, our findings reveal a transfer of charge carriers from the In2Se3 layer to the Fe3GeTe2 layer, resulting in the formation of an in-built electric field at the metal-semiconductor interface. Our work can substantially broaden the device potential of the In2Se3/Fe3GeTe2 heterojunction in future low-energy electronic devices.

Formation of p-n junction was an effective method to improve the photocatalytic performance due to its built-in electric field. However, the electric field was distributed only on the interface between two semiconductors, which was insufficient in comparison to the entire material. In this work, a multilayer TiO2–CoTiO3 p-n junction was designed and fabricated by atomic layer deposition. The charge transport and photoelectrochemical properties of multilayer TiO2–CoTiO3 films of various thicknesses are thoroughly investigated. The PL and electrochemical tests demonstrate that TiO2–CoTiO3 exhibits enhanced charge separation and transport. Additionally, the extra visible light response was achieved by introduction of CoTiO3. Also, theoretical calculations indicate that the electrons prefer to immigrate from TiO2 to CoTiO3 in a multilayer TiO2–CoTiO3 structure. Benefited from the boosted light absorption and charge transfer, the multilayer TiO2–CoTiO3 composite film exhibits a significantly increased photocurrent, much higher than pure TiO2 and a single TiO2–CoO p-n junction. This multilayer p-n junction structure opens a rational and novel way for nanostructure construction in the energy conversion region.

With the development of mobile terminals, tunable capacitors for signal processing and memristors for calculation have received a lot of attention. Combining a tunable capacitor and a memristor can improve the performance of mobile terminals and reduce space requirements. In this article, we report on Bi2NiMnO6 (BNMO) films with high dielectric tuning and nonvolatile resistive switching (RS) effects. The BNMO films are fabricated by the sol–gel method and annealed at different temperatures. It exhibits a dielectric tunability of up to 92%. This high dielectric tunability may be attributed to the modulation of the interface dipole by the electric field. When an electric field is applied, the interface dipole of the BNMO film is far away from the interface of the BNMO, and then forms a conductive channel where anions and cations are mixed. The BNMO films are found to have a double-set type effect due to its dielectric tunability properties. This work introduces an ultra-high dielectric tuning material and a new type of RS effect on BNMO thin film, which can achieve tuning and memory behavior on a device.

In this letter, a sidewall-implanted trench termination for SiC devices is proposed and experimentally demonstrated. With the p-type sidewall region implemented by tilted ion implantation, the electric field crowding at the edge of the main junction can be alleviated. Compared with the conventional trench termination, devices with the fabricated sidewall-implanted trench termination exhibits a higher breakdown voltage (BV) exceeding 1800V, as well as lower leakage current. Moreover, the minimum trench width for over 1800V blocking is significantly reduced from 14μm to 5μm. In addition, the sidewall-implanted trench termination shows stronger robustness as the dominant current path is relocated from the trench sidewall to the whole active region.

Based on localized spoof surface plasmons (LSSPs), a new microwave nondestructive testing (NDT) sensor is proposed to measure the thickness of magnetic absorbing coating on metallic surface. The metallic spiral structure (MSS) sensor fed by microstrip ring generates the LSSPs, which is used to interact with material under test (MUT) and measure the thickness of MUT. Through measurement mechanism and numerical analysis, the magnitude of the reflection coefficient is sensitive to the thickness variation of the coating. Taking a kind of magnetic absorbing film A4000 as an example, the experimental results reveal that the MSS sensor can estimate the film thickness with a range of 0.05-1.03mm, and the error is within 6%. The highest resolution can reach 0.05mm in the experiment. In fact, the formula shows that the highest resolution can reach 0.01mm. Compared with conventional monopole antenna, the microstrip ring is a new way to feed the MSS, which makes the sensor structure more stable and more compact. The sensitivity of the sensor is improved by using electric field and magnetic field to interact with the MUT together. The sensor has the advantages of high resolution, small error, stable performance and no limit to the size of the MUT.

Uniform, well-defined cadmium sulfide@cadmium selenide core/shell quantum dots (CdS@CdSe QDs) were, for the first time, successfully synthesized by a solvothermal method and chemical bath growth for photoelectrochemical activities. The as-synthesized CdS@CdSe QDs not only exhibit superior self-powered photoresponse behavior and excellent stability under ambient conditions but also display significantly improved current densities and photoresponsivity compared to those of individual CdS QDs or CdSe QDs, mainly due to the built-in electric field, and thus have great potential in the fields of renewable energy and renewable energy consumption for carbon neutrality target achievement.

Herein, we demonstrate a highly tunable enhancement and switching of nonlinear emission from all-inorganic metal halide perovskites based on an asymmetrically biased metal-insulator-semiconductor (MIS) structure. We achieve 2 orders of magnitude enhancement of the two-photon-pumped photoluminescence (TPL) from CsPbBr3 microplates with the MIS structure, due to comprehensive effects including localized field effect, trap-filling effect, and collection enhancement. In particular, taking advantage of electric-field-induced passivation/activation of Br vacancies, we realize highly tunable TPL enhancement, ranging from ∼61.2-fold to ∼370.3-fold. Moreover, we demonstrate an efficient modulation of the two-photon-pumped lasing from the MIS structure, which exhibits electric field induced switching with a high on/off ratio of 67:1. This work has opened new avenues for steering carrier transport and nonlinear emission in lead halide perovskites, which shows great promise for realizing high-efficiency and tunable nonlinear nanophotonic devices.

We propose and demonstrate a Mach-Zehnder modulator in Z-cut lithium niobate thin film (LNTF) with a vertical electric field structure. By placing the metal electrodes on top and bottom of the waveguide rather than the usual lateral configuration, the electric field is fully overlapping the optical field. Such a configuration reduces the critical requirement of electrode alignment as needed in X/Y-cut LN based devices. Both the simulation and process details to realize the proposed device are demonstrated. The measured static performance accords well with the simulations. Additionally, we developed a new method to accurately characterize the dynamic performance of the Z-cut LNTF modulator, and the measured tuning efficiency is around 8.84 pm/V. Our proposed device validates the feasibility of integrated Z-cut LNTF based modulators, and will likely extend the research area of integrated lithium niobate photonics.

In this work, a large-area MoS2/graphene barristor device, with an electrically tunable Schottky barrier height, has been studied for detection of various gaseous analytes. The Schottky barrier height could be modulated by over 0.65 eV, allowing the drain current to be tuned by many orders of magnitude. Using diluted NO2 and NH3 gases as analytes, the performance of the barristor device was compared with individual MoS2 and graphene based planar FETs, where the barristor device outperformed its counterparts in terms of response magnitude and limit of detection. Due to the atomically thin nature of MoS2 and graphene, electric field applied to one material could not be fully screened from the other one, which allowed both materials to act as a composite structure when analyte molecules interacted with the barristor device. This apparently reversed the dopant behavior of NO2 and NH3, while increasing the device sensitivity through subthreshold operation. Both conductance and capacitance based measurements are presented to highlight the charge transfer and barrier height modulation, to support the unique sensing mechanism observed in the 2D barristor device. A lower limit of detection in low ppb is established for NO2 and low ppm for NH3, which could be further tuned by altering gate-drain bias conditions.

In this article, a novel approach that mitigates partial discharge (PD) by neutralizing local electric fields with the incorporation of electrets is presented. The surface charge density requirement of electret films that enable electric field neutralization is derived and numerical analysis is performed to validate them. The fabrication process of electrets is introduced, and we experimentally demonstrate the electret films reducing PD caused by the high dv/dt of power electronics switching voltage stimuli for the first time. The PD measurements of an uncharged polyvinylidene fluoride (PVDF) film and a charged PVDF (electret) film are compared as a function of the rise time of square voltage stimuli. In addition, we compare the PD inception voltage of the two films while maintaining dv/dt at a constant value to regulate the impact of capacitive current pulses falsely being detected as PD. The results show great promise in the electret-based approach and suggest that further development of the technology may be able to completely solve PD that has been both chronic and emerging issues in the power industry.

Optical properties of GaAs/AlxGa1-xAs superlattice are studied dependent on quantum well thickness of gain region and doping density of injector layers underperformed electric field. Conduction band alignment of the superlattice is obtained by using effective mass approximation. 1d-Schrodinger formula is solved by using FDM. Intersubband transition energies, linear (nonlinear and total) absorption coefficients and linear (nonlinear and total) refractive index changes are plotted under applied electric field intensity. Intersubband transition energy of electron from second excited state to first excited state shows 147 meV. It is found that -45 kV/cm electric field intensity and 5 nm layer thickness of last quantum well of the gain region are the best values for studied structure. After that, linear absorption coefficient is investigated dependent on carrier number in the injector region under electric field. It is found that carrier number over 5 𝑥 1016 𝑐𝑚−2 can causes huge internal absorption of the radiative emission obtained in gain region due to increase in linear absorption coefficient by factor 10. As a conclusion, total absorption coefficient and total refractive index change are calculated for optimized parameters.

Heat generation in integrated circuits (ICs) has become a severe issue, which limits the utilization of miniaturized semiconductor devices in high-density 3-D IC technologies. Herein, Al₂O₃ was doped in ZrO₂ thin films by plasma-enhanced atomic layer deposition (PEALD) to enhance their antiferroelectric (AFE) characteristics for highly reliable electrocaloric (EC) cooling applications. The cycling endurance in AFE behaviors of the Al:ZrO₂ thin films under a high electric field of 5 MV/cm was significantly improved because of the enlargement of the energy bandgap with high resistance in trap-induced leakage current. Hence, the reliability of the EC effect of the 1% Al:ZrO₂ thin film was examined with a negligible change in adiabatic temperature change (Δ T) of 2.6% after a cycling endurance test of 10⁶ cycles. With the competitive cycling reliabilities in AFE and EC behaviors, devices with optimized Al₂O₃-incorporated ZrO₂ thin films show significant potential for future nanoscale cooling systems in chip-level ICs.

Lead-free dielectric materials with high breakdown electric field strength and energy density are required for pulsed power devices with high level of integration. This work describes: (Ag0.94La0.02)(Nb1-xTax)O3 lead-free antiferroelectric ceramics, which were prepared by rolling process. Following composition engineering, an outstanding energy density of 6.9 J cm-3 at electric field of 490 kV cm-1 was achieved, coupled with remarkable frequency stability (

Imaging systems that integrate multiple modalities can reveal complementary anatomic and functional information as they exploit different contrast mechanisms, which have shown great application potential and advantages in preclinical studies. A portable and easy-to-use imaging probe will be more conducive to transfer to clinical practice. Here, we present a tri-modal ultrasonic (US), photoacoustic (PA), and thermoacoustic (TA) imaging system with an excitation-reception collinear probe. The acoustic field, light field, and electric field of the probe were designed to be coaxial, realizing homogeneous illumination and high-sensitivity detection at the same detection position. US images can provide detailed information about structures, PA images can delineate the morphology of blood vessels in tissues, and TA images can reveal dielectric properties of the tissues. Moreover, phantoms and in vivo human finger experiments were performed by the tri-modal imaging system to demonstrate its performance. The results show that the tri-modal imaging system with the proposed probe has the ability to detect small breast tumors with a radius of only 2.5 mm and visualize the anatomical structure of the finger in three dimensions. Our work confirms that the tri-modal imaging system equipped with a collinear probe can be applied to a variety of different scenarios, which lays a solid foundation for the application of the tri-modality system in clinical trials.

Using first principles calculations, we have presented a short study on modulation of band structures and electronic properties of zigzag blue phosphorene (ZbPNR) and arsenene nanoribbons (ZANR) by etching the edges of NRs. We have taken the width of both NRs as N = 8 and corrugated the edges in a cosine-like manner. Optimizing every structure and further investigating their stabilities, it was seen that both the etched NRs are energetically feasible. From the computed band structures, the band gaps were seen to be increased for both the NRs on increasing number of etched layers and direct gap semiconductor nature was recorded. Highest energy gap observed were 2.26 and 2.41 eV for ZbPNR and ZANR, respectively. On further application of electric field, we observed the very interesting semiconductor-to-metallic property transition which was explained by wave function plots. Being elements of same group, a similar trend of band gaps modulations was observed for both NRs. This fascinating method of electronic property tuning of the studied NRs can be useful in various nanoscale electronic applications.

To investigate the effect of photon-induced carrier transition mechanism on switch stability, the time jitters of 2-mm-gap gallium arsenide photoconductive semiconductor switches (GaAs PCSSs) are compared when triggered by lasers of two different wavelengths, i.e., 1064 and 532 nm. The time jitter model is proposed to clarify the synergy of the multiple adjustable macroparameters of trigger conditions. The carrier valley occupation rates with respect to bias electric field are simulated, where the influence of the microprocedures, i.e., carrier generation, carrier intervalley transition, and carrier transportation, is considered. Our experimental results illustrate that the time jitter of the GaAs PCSS exhibits a nonmonotonous behavior and obtains a local minimum at ~3 kV/cm for 1064 nm; however, it shows a monotonous decrease to a constant value at about 3 kV/cm for 532 nm. Our analysis indicates that the discrepancy in GaAs PCSS time jitter is attributed to the difference in the relative fluctuation of the carrier velocity affected by the carrier valley occupation rate. This article is of great significance in optimizing the stability of GaAs PCSS and pulse power system by adjusting the macroparameters in the time jitter model.

The presence of lateral leakage through organic semi-conductive layers in organic light-emitting diodes (OLEDs) array prevents excellent performance of display application especially in high resolution one. To mitigate the impact of lateral leakage and figure out the detailed mechanism, an accurate model involving simultaneous measurements of OLED and organic thin film transistor (OTFT) is proposed. The results establish that the lateral leakage generates to the adjacent off-state devices due to a p-type thin film transistor-like effects with the cathode playing a gate function. The proposed technique reveals that higher gate voltage and source voltage brings in more serious lateral leakage, corresponding to the electric field effect. It also shows a temperature dependence when the environment has changed. The research opens the possibility of considering the influences of semi-conductive layers and parallel structural devices on more self-luminous arrays for their actual application.

This paper proposed a broadband circular waveguide rotary joint with substrate integrated coaxial line (SICL) feeder. The SICL feeder can effectively convert TEM mode in the SICL into TM210 and TM020 modes in the multi-mode substrate integrated circular cavity (SICC). The annular slot on the surface of SICC can provide strong coupling between the SICC with TM210 and TM020 modes and the circular waveguide cavity with TM010 and TM011 modes. All the modes show symmetric electric field distribution. Thus, a wide bandwidth can be obtained due to six modes and strong coupling, and stable performance can be achieved while rotating because of symmetric field distribution. Comparing with reported circular waveguide rotary joints, the proposed design has the advantages of wide bandwidth and planarization of feeder. A prototype centered at 9.35 GHz is fabricated with a 10-dB impedance matching bandwidth of 24.6% and the insertion loss is between 0.82 dB to1.65 dB.

Photocatalytic splitting water is a promising method to obtain hydrogen energy. While design and synthesis of efficient and economical photocatalysts is one of the important contents. Janus MoSSe and WSSe monolayers are efficient and wide sunlight harvesting photocatalysts due to their intrinsic vertical electric fields. So how is the photocatalytic performance of lateral MoSSe∣WSSe heterojunctions, which possesses an intra-plane interface and intrinsic vertical electric field? In the present work, the structural property, electronic characteristic, optical property, and photocatalytic application of MoSSe∣WSSe lateral heterojunctions are systematically investigated. It is found that both zigzag and armchair configurations are semiconductors with suitable bandgaps of ∼ 1.60 eV. Besides, they possess a type-II band alignment where electrons tend to accumulate at the coupling interface of MoSSe side and holes at WSSe side, giving rise to a paralleled electric field in heterojunctions, which can largely promote the separation of photo-generated carriers. More remarkably, these heterojunctions exhibit pronounced solar-spectrum absorption efficiency, proper valence, and conduction band positions by initializing the redox reactions of H2O and high carrier mobility. Intriguingly, the zigzag MoSSe∣WSSe heterojunction has a better photocatalytic performance in an acidic environment, and the armchair MoSSe∣WSSe prefers to produce H2 and O2 in a neutral environment. These fascinating properties render the intra-plane MoSSe∣WSSe heterojunctions as the wide solar harvesting photocatalysts in further overall water splitting.

A circularly polarized (CP) meander loop antenna design for GNSS applications is presented. The antenna size is 52.552.50.76 mm3 and it is placed 10 mm above a 100100 mm2 metal plane. The proposed antenna utilizes a meandered loop antenna and have applied a perturbed element into the loop to excite two equal electric fields with near 90 phase difference, thereby radiating a good CP radiation. In addition, a triangular patch is loaded to the two diagonal corners of the loop are for improving the CP performances, as well as maintaining its CP radiation even under the interference of a large metal surface beneath it. The simulated 10-dB impedance bandwidth of proposed antenna was 2.2% (1.5571.593 GHz), and the measured one was 2.4% (1.5531.591 GHz). The simulated and measured 3-dB AR bandwidths were 0.8% (1.571.583 GHz) and 1.02% (1.5671.583 GHz), respectively. Lastly, the proposed antenna is suitable for GNSS application that has large metal surface/ground, such as the roof of a vehicle.

Solar blind ultraviolet (SBUV) self-powered photodetectors (PDs) have a great number of applications in civil and military exploration. Ga2O3 is a prospective candidate for SBUV detection owing to its reasonable bandgap corresponding to the SBUV waveband. Nevertheless, the previously reported Ga2O3 photovoltaic devices had low photoresponse performance and were still far from the demands of practical application. Herein, we propose an idea of using spiro-MeOTAD (spiro) as the SBUV transparent conductive layer to construct p-i-n PDs (p-spiro/Ga2O3/n-Si). With the aid of double built-in electric fields, the designed p-i-n PDs could operate without any external power source. Furtherly, the influence of spiro thickness on improving the photoelectric performance of devices is investigated in detail and the optimum device is achieved, translating to a peak responsivity of 192 mA/W upon a weak 254 nm light illumination of 2 μW/cm2 at zero bias. In addition, the I-t curve of our PD shows binary response characteristics and a four-stage current response behavior under a small forward bias, and also, its underlying working mechanism is analyzed. In sum, this newly developed device presents great potential for booming the high energy-efficient optoelectronic devices in the short run.

Мы живем в мире высоких энергетических технологий, способных передавать электрическую энергию на большие расстояния. Эту энергию невозможно сосредоточить только внутри передающих энергетических систем. Она выплескивается наружу в виде электрических полей. Эти электрические поля неблагоприятно воздействуют на окружающую среду, технические и биологические объекты. В связи с этим необходимо контролировать уровни электрических полей, важной характеристикой которых является напряженность электрического поля. Для восприятия электрического поля необходимы датчики напряженности электрического поля. Существующие датчики неудобны в эксплуатации и имеют высокую погрешность восприятия напряженности электрического поля, достигающую ± 20%. Bыдвигается идея создания универсального датчика нового вида, относящeгося к виду сдвоенных датчиков. Его универсальность заключается в том, что он воплощает в себе все виды известных датчиков - одинарные, сдвоенные и теперь еще двойные. Погрешность восприятия напряженности неоднородного электрического поля сдвоенных датчиков не превышает +5 % во всем пространственном диапазоне измерения 0£ a £1. При этом расстояние d до источника поля ограничено только радиусом сферического основания датчика, т.е. d » R , в то время как для датчиков, входящих в состав сдвоенного датчика, в том же пространственном диапазоне измерение погрешности составляет ± 35 %. Используя сдвоенный датчик, можно добиться значительного повышения точности измерения напряженности неоднородных электрических полей в широком пространственном диапазоне измерений по сравнению с известными датчиками We live in a world of high energy technologies capable of transmitting electrical energy over long distances. This energy cannot be concentrated only within the transmitting energy systems. It spills out in the form of electric fields. These electric fields adversely affect the environment, technical and biological objects. In this regard, it is necessary to control the levels of electric fields, an important characteristic of which is the strength of the electric field. Sensors of the electric field strength are required to sense the electric field. The existing sensors are inconvenient in operation and have a high error in the perception of the electric field strength, reaching ± 20%. In the work under consideration, the idea of creating a universal sensor of a new type, related to the type of dual sensors, is put forward. Its versatility lies in the fact that it embodies all types of known sensors - single, twin, and now dual. The error in the perception of the intensity of the inhomogeneous electric field of the dual sensors does not exceed + 5% in the entire spatial measurement range 0£ a £1. In this case, the distance d to the field source is limited only by the radius of the spherical base of the sensor, i.e. d » R . At the same time, for sensors that are part of a dual sensor in the same spatial measurement range, the error is ± 35%. Using a dual sensor, it is possible to achieve a significant increase in the accuracy of measuring the strength of inhomogeneous electric fields in a wide spatial measurement range in comparison with known sensors.

Droplet-based microfluidics is a modular platform in high-throughput single cell and small sample analyses. However, this droplet microfluidic system was widely fabricated using soft lithography or glass capillaries, which is expensive and technically demanding for various applications, limiting use in resource-poor settings. Besides, the variation in droplet size is also restricted due to the limitations on the operating forces that the paper-based platform is able to withstand. Herein we develop a fully integrated paper-based droplet microfluidic platform for conducting droplet generation and cell encapsulation in independent aqueous droplets dispersed in a carrier oil by incorporating electric fields. Through imposing an electric field, the droplet size would decrease with increasing the electric filed and smaller droplets can be produced at high applied voltage. The droplet diameter can be adjusted by the ratio of inner and outer flow velocities as well as the applied electric field. We also demonstrated the proof of concept encapsulation application of our paper device by encapsulating yeast cells under an electric field. Using a simple wax printing method, carbon electrodes can be integrated on the paper. The integrated paper-based microfluidic platform can be fabricated easily and conducted outside of centralized laboratories. This microfluidic system shows great potential in drug and cell investigations by encapsulating cells in resource-limited environments. This article is protected by copyright. All rights reserved.