Device Processing Research Articles

Integrated optical switches based on Kerr symmetry breaking in microresonators

With the rapid development of the Internet of Things and big data, integrated optical switches are gaining prominence for applications in on-chip optical computing, optical memories, and optical communications. Here, we propose a novel approach for on-chip optical switches by utilizing the nonlinear optical Kerr effect induced spontaneous symmetry breaking (SSB), which leads to two distinct states of counterpropagating light in ring resonators. This technique is based on our first experimental observation of on-chip symmetry breaking in a high-Q (9.4×106) silicon nitride resonator with a measured SSB threshold power of approximately 3.9 mW. We further explore the influence of varying pump powers and frequency detunings on the performance of SSB-induced optical switches. Our work provides insights into the development of new types of photonic data processing devices and provides an innovative approach for the future implementation of on-chip optical memories.

Meta-Device for Field-of-View Tunability via Adaptive Optical Spatial Differentiation.

Optical edge detection is a crucial optical analog computing method in fundamental artificial intelligence, machine vision, and image recognition, owing to its advantages of parallel processing, high computing speed, and low energy consumption. Field-of-view-tunable edge detection is particularly significant for detecting a broader range of objects, enhancing both practicality and flexibility. In this work, a novel approach-adaptive optical spatial differentiation is proposed for field-of-view-tunable edge detection. This method improves the ability to acquire spatial information and facilitates edge detection over a wider angular range. The adaptive optical spatial differentiation meta-device relies on two core components: the spatial differentiation dielectric metasurface and the adaptive liquid prism. The meta-device is shown to function as a highly efficient (≈85%) isotropic spatial differentiator, operating across the entire visible spectrum (400 to 700nm) within a wide-angle object space, expanding up to 4.5 times the original field of view. The proposed scheme presents new opportunities for efficient, flexible, high-capacity integrated data processing and imaging devices. And simultaneously provides a novel optical analog computing architecture for the next generation of wide field-of-view phase contrast microscopy.

Accelerated Modeling of Transients in Electromagnetic Devices Based on Magnetoelectric Substitution Circuits

During switching in electrical systems, transient electromagnetic processes occur. The resulting dangerous current surges are best studied by computer simulation. However, the time required for computer simulation of such processes is significant for complex electromagnetic devices, which is undesirable. The use of spectral methods can significantly speed up the calculation of transient processes and ensure high accuracy. At present, we are not aware of publications showing the use of spectral methods for calculating transient processes in electromagnetic devices containing ferromagnetic cores. The purpose of the work: The objective of this work is to develop a highly effective method for calculating electromagnetic transient processes in a coil with a ferromagnetic magnetic core connected to a voltage source. The method involves the use of nonlinear magnetoelectric substitution circuits for electromagnetic devices and a spectral method for representing solution functions using orthogonal polynomials. Additionally, a schematic model for applying the spectral method is developed. Obtained Results: A method for calculating transients in magnetoelectric circuits based on approximating solution functions with algebraic orthogonal polynomial series is proposed and studied. This helps to transform integro-differential state equations into linear algebraic equations for the representations of the solution functions. The developed schematic model simplifies the use of the calculation method. Representations of true electric and magnetic current functions are interpreted as direct currents in the proposed substitution circuit. Based on these methods, a computer program is created to simulate transient processes in a magnetoelectric circuit. Comparing the application of various polynomials enables the selection of the optimal polynomial type. The proposed method has advantages over other known methods. These advantages include reducing the simulation time for electromagnetic transient processes (in the examples considered, by more than 12 times than calculations using the implicit Euler method) while ensuring the same level of accuracy. The simulation of processes over a long time interval demonstrate error reduction and stabilization. This indicates the potential of the proposed method for simulating processes in more complex electromagnetic devices, (for example, transformers).

Electrostatic discharge failure and protection of single-walled carbon nanotube field-effect transistors

Abstract Carbon nanotube based field effect transistors (CNT-FETs) have been considered as a preferred alternative to the traditional Si-based MOSFETs. Here we investigated the electrostatic discharge (ESD) failure characteristics of single-walled CNT (SWCNT) FET. In ESD event, the instantaneous high current will generate an amount of heat in the CNT-FET channel resulting in its thermal failure owing to its randomly aligned SWCNT networks. The CNT-FET failure mechanism and its ESD characteristics with various key parameters are studied in detail. These insights provide new ideas and a guidance for the research and application of CNT-FETs. In order to achieve a full chip ESD protection network for CNT chips, we referred to commonly used ESD devices in silicon-based processes and designed CNT based ESD devices, including GD-CNT-FET (Gated-VDD CNT-FET) and RC-CNT-FET (RC trigger CNT-FET). CNT-FET with randomly aligned SWCNT networks, whose failure current level is only about 50µA/µm, needs larger areas to achieve effective ESD protection.

Dimethylacridine based emitters for non-doped organic light-emitting diodes with improved efficiency.

Organic light-emitting diodes (OLEDs) has been attracting much extensive interest owing to their advantages of high-definition and flexible displays. Many advances have been focused on boosting the efficiency and stability. Two innovative dimethylacridine-based emitters,1,1,2,2-tetrakis(4- (2,7-di-tert-butyl-9,9-dimethylacridin-10(9H)-yl)phenyl ethene (AcTPE), and bis(4-(2,7-di-tert-butyl-9,9-dimethylacridin-10(9H)-yl)phenyl)methanone (Ac2BP) were designed and synthesized, in which TPE-baesed AcTPE presents AIE properties, and with the phenyl as spacer between the DMAC and carbony, aryl-ketone-based Ac2BP doesn't show AIE properties due to the absence of restriction of intramolecular rotations. As the electron-withdrawing ability of carbonyl, well-matched energy levels of the Ac2BP improve carriers transfer and hole injecting process in devices, resulting an efficient green emission with a maximum PE of of 5.64 lm W-1, a EQE of 10.56% and a maximum CE of 18.27 cd A-1. They are much higher than that of AcTPE-based devices (3.45 cd A-1, 1.18 lm W-1, and 1.46%). This study provides a promising design strategy for efficient OLED emitters of aryl-ketone-architecture.

The influence of teachers' ICT competence on children's digital literacy abilities

The use of digital devices in the learning process is intended to provide convenience for teachers in presenting quality learning for children. Therefore, digital literacy is very much needed by teachers and prospective teachers in order to optimize children's development. This study uses a quantitative research design. The population in this study amounted to 9 respondents from various areas of Surabaya, while the sample in this study was obtained by 45 respondents with the research subjects being kindergarten teachers in the Surabaya area. The sampling technique used was purposive sampling. The data analysis technique used cluster sampling technique. The overall research results show that teacher ICT competence has an effect on children's digital literacy skills, which shows that the variable X teacher ICT competence has a t count of 2.654, which means it is greater than the t table which is 2.01669, and a significant value of 0.011 is smaller than 0.05. So it can be concluded that H1 is accepted so that variable X has a significant effect on variable Y, namely children's digital literacy skills. These results are also supported by the conformity of the results on each question item covering teacher competence in using digital devices in their learning. With the presence of digital devices as a learning resource, it produces children's ability to learn independently and teach children to utilize digital devices to improve knowledge and skills according to their age.

Modeling the composite fuel’s flow and combustion process in a combined burner device

Modeling the composite fuel’s flow and combustion process in a combined burner device

Management of risks linked to the sterilization of reusable medical devices in dentistry

The aim of this study was to analyze the risks associated with the sterilization process for reusable medical devices (RMD) in stomatology, by applying the FMECA method, with a view to implementing the necessary corrective and preventive actions necessary to secure this process. The study, which was descriptive, took place between June and July 2024 in the medicine and dental surgery department of our hospital and concerned the moist heat sterilization process of RMD. The study began by defining its scope and the formation of the work team, followed by the functional analysis of the process, the identification of the failure modes (FM), the definition of the rating scales, the rating of the FM and finally the calculation of the criticality index and the development of the action plan. A total of 64 FM were identified, including 14 of high criticality, 16 of medium criticality and 34 of low criticality. The pre-disinfection and cleaning stage generated the most failures, particularly those of high criticality. High criticality FM were subject to a set of corrective and preventive actions. A new map of the sterilization process highlighting a 'forward march' flow has been proposed. Our FMECA made it possible to highlight several FM and propose an appropriate action plan. A second FMECA would still be interesting to evaluate the reduction in the overall criticality of our process.

다가구 주택의 범죄 예방을 위한 위험 요인 분석에 관한 연구

The increase in single-person households is one of the phenomena that is attracting attention in modern society. This study analyzes the risk factors of living in multi-family houses and studies and analyzes how safety facilities are installed and managed to propose improvement measures. The survey was conducted by deriving 7 detailed factors, including the experience of crime damage, fear of crime, and installation of safety facilities, etc. In addition, the installation status of image information processing devices, which are physical safety facilities, was investigated and analyzed. As a result of the survey, the improvement of the risk exposure to crime and the installation and maintenance of safety facilities were investigated as very important factors. The fear of crime did not show significant differences by age or household size, and it was found that the fear of all types of crime has increased. Although crime prevention standards have been established as related laws, multi-family houses are classified as recommended applications, and the blind spots of crime have been identified. Therefore, it is proposed that the crime prevention standards are mandatory for multi-family houses. In addition, it proposes the necessity of enacting laws that can enforce management because the maintenance standards of image information processing devices, which are physical safety facilities, do not have legal regulations. This study emphasizes the importance of residential safety and living environment, and believes that it can be used as an important study that can greatly affect the safety and welfare of society.

Identifying and understanding the nonlinear behavior of memristive devices

AbstractNonlinearity is a crucial characteristic for implementing hardware security primitives or neuromorphic computing systems. The main feature of all memristive devices is this nonlinear behavior observed in their current-voltage characteristics. To comprehend the nonlinear behavior, we have to understand the coexistence of resistive, capacitive, and inertia (virtual inductive) effects in these devices. These effects originate from corresponding physical and chemical processes in memristive devices. A physics-inspired compact model is employed to model and simulate interface-type RRAMs such as Au/BiFeO$$_{3}$$/Pt/Ti, Au/Nb$$_{\textrm{x}}$$O$$_{\textrm{y}}$$/Al$$_{2}$$O$$_{3}$$/Nb, while accounting for the modeling of capacitive and inertia effects. The simulated current-voltage characteristics align well with experimental data and accurately capture the non-zero crossing hysteresis generated by capacitive and inductive effects. This study examines the response of two devices to increasing frequencies, revealing a shift in their nonlinear behavior characterized by a reduced hysteresis range Fourier series analysis utilizing a sinusoidal input voltage of varying amplitudes and frequencies indicates harmonics or frequency components that considerably influence the functioning of RRAMs. Moreover, we propose and demonstrate the use of the frequency spectra as one of the fingerprints for memristive devices.

Structural improvement of a mobile device for pre-heated treatment of vegetable raw materials

The object of this study is the heat treatment of multicomponent masses, for example, Jerusalem artichoke, pumpkin, and black chokeberry, during thickening and drying in an improved mobile functional apparatus for preliminary heat operations. The engineering solution is aimed at the implementation of resource-saving preliminary thermal operations of plant raw materials on mobile functional equipment. The structural difference of the device for the preliminary heat treatment of plant raw materials is the presence of a mobile platform with a carousel arrangement of rolling containers with changeable working elements. The device provides simultaneous implementation of thermal operations in three functional containers. The vacuum compartment and the steam generator with flexible technical lines are connected to functional tanks equipped with bubbler disks to improve heat transfer. The central platform has a microprocessor-based automatic control unit and a spring mechanism for lifting the cover equipped with Peltier elements for secondary heat conversion. The tanks are heated by a film resistive electric heater. Peltier elements are mounted on the inner surface of the cover to convert secondary heat for autonomous operation of the fan. For preliminary heat treatment of liquid media, the functional container is additionally equipped with a stirrer with a heated surface (the usable area of the thermal surface is 0.28 m2). The duration of reaching a stationary temperature regime (50 °С) of the multicomponent mass (Jerusalem artichoke – 50 %, pumpkin – 40 %, and chokeberry – 10 %) in a mobile device is 31.4 % less than in a classic design. The duration of the drying process in the functional device is 40 minutes, and in the conventional KVM-150 device – 60 minutes. A 1.8-fold decrease in the specific metal capacity was established. Total heat losses are reduced by 1.24 times, and the usable heating surface is increased by 1.3 times

Topology and PT symmetry in a non-Hermitian Su–Schrieffer–Heeger chain with periodic hopping modulation

We study the effect of periodic hopping modulation in a Su-Schrieffer-Heeger (SSH) chain with an additional onsite staggered imaginary potential (of strengthγ). Such dissipative, non-Hermitian (NH) extension amply modifies the features of the topological trivial phase (TTP) and the topological nontrivial phase (TNP) of the SSH chain, more so with the periodic hopping distribution. Generally a weak NH potential can respect the parity-time (PT) symmetry keeping the energy eigenvalues real, while a strong potential breaksPTconservation leading to imaginary edge state and complex bulk state energies in the system. We find that the non-zero energy in-gap states, that appear due to periodic hopping modulations even in theγ = 0 limit, take purely real or purely imaginary eigenvalues depending on the strength of bothγand Δ (dimerization parameter). The localization of topological edge states (in-gap states) at the boundaries are investigated that reveals extended nature not only near topological transitions (further away from|Δ/t|=1) but also near the unmodulated limit ofΔ=0. Moreover, localization of the bulk states is observed at the maximally dimerized limit of|Δ/t|=1, which increases further withγ. These dissipative features can offer additional tunability in modulating the gain-loss contrast in optical systems or in designing various quantum information processing and storage devices.

On the Exceptional Points effect in All-Dielectric Metasurface

All-dielectric non-Hermitian structures make it possible to obtain unique effect like the appearance of the exceptional points (EP). A system at EP is sensitive to a small perturbation of refractive index, which can be widely used in different ways, such as EP-based sensors, optical amplifiers, laser gyroscopes and other fields. In this study, we investigate an exceptional point in two-rectangle system with varying opening angle which can be defined as a structure with only in-plane symmetry breaking. Furthermore, the effect dependance of geometry parameters has been studied. The main advantage of our geometric approach is the simplified way to experimental control an EP. Consequently, this effect has the potential to significantly simplify the manufacturing process of photonic devices with diverse functionalities.

Paper-Based Device for Phenolic Content Determination in Tea Extracts.

Phenolic compounds garner interest in developing medicines, nutraceuticals, and cosmeceuticals based on natural products. The quantity of phenolic compounds in a sample is commonly determined via spectrophotometry; however, this instrumented technique is relatively laborious and time consuming and requires a large amount of reagents. This work aimed to develop a simple, point-of-need colorimetric sensor to rapidly determine total phenolic content (TPC) in tea extracts. We developed a radial paper-based analytical device (PAD) for TPC determination based on the established colorimetric reaction between the Folin-Ciocâlteu reagent and phenols. The PAD was designed to enable quantitative (with image capturing device and color processing software) and semiquantitative (using a color palette reference card) determinations. Analytical performance and stability of the PAD were evaluated based on the color responses. The PAD was successfully applied for the determination of phenolics in tea extracts obtained using several polar protic solvents, including water, methanol, and ethanol, with satisfactory accuracy (recovery of 95.5%-104%, 110%-116%, and 104%-110%, respectively) and precision (RSD < 9%). The obtained TPC values also agreed with those from visible spectrophotometry. Semiquantitative determination using the color reference card with three categories of TPC level (i.e., 0-100, 100-500, and 500-1000 mg gallic acid equivalent/L) provided > 95% accuracy. The devices were the most stable when stored at 4°C in a light-protected, vacuum-sealed container. The proposed PAD is promising for simple, rapid (~10-20 min), and accurate estimation of TPC in plant extracts.

The Resampling Methods Direct Sequence Spread Spectrum Signal’s Demodulator Implementation

Relevance. The direct spread spectrum signals are widely used in navigation and communication systems recently. These signals prevail in modern satellite navigation systems and are used in various communication systems with code division multiplexing in particularly. In this regard, the tasks of building direct spread spectrum signals’ demodulators have the key importance. Mach importance in the construction of demodulators is the problem chip rate variability.The purpose of the study is to propose a demodulator structure focused on solving this problem.Methods. The research is based on computer modeling methods.Decision. The paper proposes an approach to the construction of the direct spread spectrum signal’s demodulators based on modern methods of digital signal processing. It is shown that the main advantage of the proposed approach is the possibility of rebuilding the variable chip rate demodulators. Based on the results obtained, a scheme for the direct spread spectrum signals demodulator using resampling methods is proposed. Resampling, in turn, is implemented on the basis of polynomial interpolation using Lagrange polynomials. The structure of the resampler is proposed, similar to the structure of an interpolating filter with a finite impulse response. The presented simulation results show the effectiveness of the proposed approach.Novelty. It seems that the currently common methods of implementing direct spread spectrum signal in terms of delay synchronization do not sufficiently meet modern requirements. The implementation of delay synchronization schemes based on resampling is practically not discussed in well-known works. At the same time, modern methods and devices of digital signal processing make it possible to ensure an effective hardware implementation of the scheme in question. In this context, the approach proposed in the paper to the construction of demodulators seems to be very relevant.Significance. The results of the work can be used in the construction with direct spread spectrum signals’ demodulators for a wide range of communication and navigation systems. The synchronous sampling structure proposed in this paper is very promising, especially for variable chip rate demodulators.

Miniaturized IPD-based bandpass filter chip with edge self-coupled SRR and mixed coupling structure for 5G new radio

ABSTRACT A miniaturised millimetre-wave bandpass filter chip based on the integrated passive device (IPD) process for 5 G new radio is proposed in this paper. Two techniques are utilised to minimise the circuit footprint. Firstly, the innovative edge self-coupled split ring resonator (ES-SRR) is proposed, which incorporates a self-coupled effect by narrowing the gap between the vertical microstrip line and the two split stubs. The theoretical model of the ES-SRR is examined to identify its resonating characteristics. Secondly, the magnetic dominant mixed-coupling structure is implemented in the planar filter by meticulously adjusting the resonator line widths. This configuration generates two transmission zeros at each side of the passband. To demonstrate their effectiveness, a sixth-order bandpass filter, operating within the frequency range of 24.25–29.5 GHz, is simulated and fabricated using 100-µm-thick GaAs IPD technology. Experimental results reveal an insertion loss of 2.95 dB and a minimum return loss of 17 dB, achieving a fractional bandwidth of 21%. Notably, the filter exhibits two transmission zeros at 21 GHz and 33 GHz with rejection levels of 55 dB and 60 dB, respectively.

Self-Oscillations Of Current In Silicon: Physical Principles, Mechanisms And Application

The article discusses self-oscillatory processes in silicon semiconductor devices, such as diodes and transistors, based on nonlinear effects of interaction of electric current and voltage. Particular attention is paid to the physical mechanisms of selfoscillations, including avalanche breakdown, thermal and electrical feedback, as well as their impact on the operation of silicon devices. Examples of the application of selfoscillatory modes in high-frequency signal generators and radio engineering devices are given. Methods for eliminating unwanted oscillations to ensure stable operation of circuits are also discussed

Research Progress on the Recycle and Reuse of Wasted Aluminum Substrates of CTP Plates

Recycling and reuse of wasted materials is a key topic in materials research, providing a new material recycling path for green manufacturing. As a national pillar industry, the greening and intelligent upgrading of the printing industry is an inevitable trend in the development of modern printing. To better implement the national “dual-carbon strategy” and cultivate new quality productivity, this paper presents a systematic literature review on the research progress of the recycling and reuse techniques of used aluminum substrates of CTP plates for offset printing. Analysis of existing industry data and literature shows that aluminum substrate of used CTP plates meets the recycle size and required physical and chemical characteristics, but the current research has not yet fully taken into account the integration of technical innovation in the recycling and reuse of aluminum substrate of used CTP plates. Based on material eco-cycling perspectives such as sustainable material utilization design, wasted material recycling device and multi-material fine separation process, this paper provides a unique outlook on the integrated development trend of recycling and reuse of aluminum substrates of used CTP plates, and provides greening case references for the safe management of wasted materials in the modern offset printing industry.

Raman intensity enhancement of Raman active and forbidden modes induced by naturally occurred hot spot at GaAs edge

Abstract Edge structures are ubiquitous in the processing and fabrication of various optoelectronic devices. Novel physical properties and enhanced light-matter interactions are anticipated to occur at crystal edges due to its broken spatial translational symmetry. However, the intensity of first-order Raman scattering at crystal edges has been rarely explored, although the mechanical stress and edge characteristics have been thoroughly studied by the Raman peak shift and the spectral features of the edge-related Raman modes. Here, by taking GaAs crystal with a well-defined edge as an example, we reveal the intensity enhancement of Raman-active modes and the emergence of Raman-forbidden modes under specific polarization Raman configurations at the edge. This is attributed to the presence of hot spot at the edge, due to the redistributed electromagnetic fields and electromagnetic wave propagations of incident laser and Raman signal near the edge, which are confirmed by the finite-difference time-domain simulations. Spatially-resolved Raman intensity of both Raman-active and Raman-forbidden modes near the edge is calculated based on the redistributed electromagnetic fields, which quantitatively reproduce the corresponding experimental result. These findings offer new insights into the intensity enhancement of Raman scattering at crystal edges and presents a new avenue to manipulate the light-matter interactions of crystal by manufacturing various types of edges and to characterize the edge structures in photonic and optoelectronic devices.

PIROLIZ REAKTORINING QOVURG‘ALI SIRTI ORQALI ISSIQLIK UZATISH SAMARADORLIGINI HISOBLASH

In this article, the thermal parameters of the biomass pyrolysis thermal processing device were calculated. Also, the flow of flue gas at a temperature of 500-600 ℃ during the pyrolysis process, its movement on the ribbed surfaces of the pyrolysis reactor, and its effect on the water boiler on the outer wall of the reactor were studied. The bioreactor is made of the "pipe in a pipe" type, pyrolysis of biomass takes place in its inner pipe, and water is heated in the outer pipe due to the heat lost to the environment. At the same time, the internal pipe of the reactor allows obtaining gaseous fuel by thermal processing of biomass, and the heat in the external pipe of the boiler solves the problem of providing consumers with hot water in the heating system. The proposed device thermally processes agricultural biomass waste and provides autonomous consumers with alternative fuels and thermal energy at the same time.