Copper Wire Research Articles

Recycling of enamelled copper wire from end-of-life electric motor via room temperature methanolysis

Polyester enamelled copper wire plays an important role in the manufacturing of electric motors. In line with the electrification of transport, the demand for electric motors and the future waste generated from their end-of-life cannot be ignored. The waste from the polyester enamelled copper wire is expected to increase steadily. Methods proposed by researchers are mainly focused on thermal treatment to either pyrolyse or burn off the polyester enamel. However, thermal treatments fail to consider the potential risk of air pollution and to recover the polyester enamel.In this manuscript, we propose two-stage processes comprised of methanol washing and room temperature methanolysis with dichloromethane as co-solvent and K2CO3 as catalyst to delaminate multilayered type enamelled copper wire. The methanol washing recovers polyvinyl butyral as it is, via dissolution. Whereas the methanolysis products are dimethyl terephthalate (DMT) and dimethyl isophthalate (DMI) which are precursors to the polyester and could be used to make new polyester. At room temperature, the parameters of solid to liquid, DCM to methanol, and K2CO3 to Cuwire ratio, of 500 g/L, 1.00 mol/mol, and 0.10 wt%, respectively, allow complete removal of polyester enamel in 24 h. The methanolysis parameters described manage to give a modest DMT and DMI yield of 86.0% and 92.2%, respectively. The reaction time can be sped up by increasing the temperature by 10 °C, leading to complete depolymerisation in 4 h. Compared to thermal treatment, the proposed method requires 80.7% lower energy with the products contained within the solution.

Effects of Copper(II) Oxide on the Co-Pyrolysis of Waste Polyester Enameled Wires and Poly(vinyl chloride).

The emission of chlorinated pollutants is one of the main problems when recovering copper (Cu) via pyrolysis from waste enameled wires. This is mainly attributed to other wastes which possess high poly(vinyl chloride) content, such as electrical wires and cables, which are often recycled together with enameled copper wires. In this research, to control the chlorinated pollutants, copper(II) oxide (CuO) was chosen and demonstrated to be an efficient dechlorinating agent, and CuO did not introduce any impurities that influence the quality of the recovered Cu. The pyrolysis and co-pyrolysis of polyester enameled wires, PVC, and CuO were investigated, and special attention was paid to chlorinated compounds in released pyrolytic products. In particular, the co-pyrolysis of this ternary mixture was studied for the first time, and some new pyrolysis behaviors were discovered. For example, the results of Py-GC/MS analyses showed that the addition of CuO removed about 75% of the chloro-organic products, the main types of which were chloroaromatic compounds rather than the more toxic chloroesters. Moreover, pyrolysis gases were collected and characterized via ion chromatography, and the results showed that the chlorine content in the pyrolysis gases decreased by about 71%. TG analysis indicated that CuO only minimally affected the pyrolysis of polyester paint. However, through the chlorine fixation effect, CuO influenced the dechlorination and dehydrochlorination of PVC, as well as secondary reactions between HCl and pyrolysis products of polyester paint, therefore changing the products and behaviors of co-pyrolysis. Mechanism of reducing chlorine-containing pollutants and reaction mechanism of forming typical pyrolysis products closely correlated to the effects of CuO were also proposed, providing theoretical guidance for the recycling of waste enameled wires.

Secondary electron yield (SEY) evolution of laser processed oxygen-free high conductivity copper induced by different ultrasonic cleaning durations

Laser treated material surface has highly regular curves and greatly reduces the secondary electron yield of surface. As one of the most typically used materials in the vacuum system of particle accelerators, the surface of oxygen-free high conductivity copper (OFHC) is processed by laser. Moreover, ultrasonic cleaning can effectively remove powders and impurities produced by laser ablation. The secondary electron yield (SEY), surface morphology and surface composition of laser treated oxygen-free copper samples before and after ultrasonic cleaning were compared. Experiments were conducted by using the secondary electron yield test device, X-ray diffractometer, X-ray photoelectron spectroscopy, and scanning electron microscope to characterize the SEY, crystal structures, surface composition and surface morphology of laser-treated oxygen-free copper samples, respectively. The SEY evolution of the samples was investigated and analyzed at electron doses of 7.6 × 10−6 C mm−2: after 15-min ultrasonic cleaning, the δmax of sample #1, #2 and #3 increased from 1.09, 1.23, and 1.38 to 1.19, 1.2, and 1.63, respectively, with the maximum increase of 18.12 %. Ultrasonic cleaning could greatly reduce the accumulation of spherical particles and the fibrous or flocculent structures produced by laser processing, thereby reducing the capture of secondary electrons.

Development of a microelectrode for simultaneous <i>in vivo</i> calcium and electrophysiological recording of hippocampal neuronal activity

Calcium (Ca2+) imaging is a commonly utilized neuroscience technique for in vivo recording of neuronal activity. It involves the optical measurement of calcium concentration using genetically encoded calcium indicators (GECI) [1]. However, the kinetics of changes in the fluorescence of GECI are relatively slow and limited by the biophysics of the calcium binding [2]. In response to single action potentials (APs) in pyramidal neurons, most of the widely used GECI have a fluorescence half-life of approximately 100 ms [3]. As a result, GECI cannot provide complete information about the dynamics of neural ensembles. To address this issue, new variants of GECI, such as jGCaMP7 [3], and jGCaMP8 [4], have been developed, or genetically encoded voltage indicators (GEVI), such as JEDI-2P [5], have been utilized. However, the speed of GECI or GEVI is still lower than that of electrophysiological registration methods. Thus, we have designed a microelectrode that can be utilized with a gradient lens for in vivo calcium imaging with a miniscope. The miniscope is a miniature microscope for single photon epifluorescence Ca2+ imaging, which enables recording of neuronal activity in freely moving laboratory animals, unlike the traditionally used two-photon imaging technique. The miniscope utilizes gradient-index (GRIN) lenses that are implanted directly into the brain of a laboratory animal, instead of a conventional lens. The gradient lens is a transparent cylinder with a diameter of 1.8 mm and a length of 3.8 mm. To facilitate electrophysiological recording, we developed a microelectrode that can be aligned with a GRIN lens. The microelectrode is a three-layer structure consisting of: 1) a polyimide film, 2) conductive copper tracks deposited through thermoforming, and 3) a polyimide film with cutouts for pads. On one side of the microelectrode, there are 12 gold-plated conductive contacts for registering local field potentials, while on the other side, a similar number of conductive tracks are present for connecting to a connector that transmits data to the processing board. The flexible microelectrode is wrapped around a gradient lens and fixed using thermoforming, after which it is implanted in the animal's brain. Using the developed microelectrode, our aim is to perform a comparative analysis of the calcium and electrophysiological activity of hippocampal neurons in freely moving wild-type mice and in a mouse model of Alzheimer's disease. This study will enable the identification of any abnormalities in Alzheimer's disease at the level of neural ensembles and may suggest new treatment approaches or mechanisms for the development of the progressive memory loss pathology associated with this disease. We would like to express our gratitude to Anastasia Viktorovna Bolshakova for her administrative assistance, and to the staff of the Laboratory of Molecular Neurodegeneration for their invaluable help and advices.

THE DESIGN OF THE POWER SUPPLY CURRENT LEADS TO A HIGH-TEMPERATURE SUPERCONDUCTING ELECTROMAGNET

The paper presents a theoretical and experimental analysis of thermal conditions imposed on the power supply conductor for an HTS YBCO-type high magnetic field electromagnet. For thermal stability during the operation of the electromagnet, it is essential to lower the heat flux from outside the system. The heat from the surrounding environment to the HTS winding is limited by using an adequately sized cryogenic system and the proper design of the current leads. The HTS winding and current leads are cooled with a two-stage GM cryocooler. If the power supply conductor's conductive heat flux exceeds the cryocooler’s heat load, the temperature of the HTS winding will increase, and system instability may occur. The power supply conductors are of two types: copper conductors and mixed HTS conductors. This work analyzes HTS conductors and junctions of HTS tape with copper terminals and their contribution to the cryocooler’s total heat load. Using HTS conductors reduces Joule heat when current passes through them (approx. 300 A) and the conductive heat flux to the HTS windings. Resistance for various soldering alloys was experimentally evaluated to evaluate the Joule heat of the junctions between HTS conductors and copper terminals.

A computational investigation of electron transport in defected Cu thin films

Interconnects are a key component of integrated circuits (IC) and play a major role in the speed and power consumption of an IC. While surface roughness is essential for ensuring adhesion to other components in an IC, it also increases electron scattering at the surface, which can dramatically increase resistivity. Barrier layers have been introduced to mitigate the effect of rough Cu surfaces, but explanations of their behavior are varied. Using a combination of density functional theory (DFT) and the non-equilibrium Green’s function technique in conjunction with DFT (NEGF-DFT), our work aims to identify key tradeoffs between surface roughness profiles and electronic performance in copper wire interconnects, and how barrier layer atoms affect conductance across the Cu surface. We find that by removing atoms from the surface, the current allowed across the film is reduced to that of a thinner pristine film, but that as the voltage is increased the defected film recovers some of the conductance of the pristine system. By replacing the vacancy with a substituent atom (Ag, Al, Au, Co, Ir, Ni, Pd, Rh, Sn, Zn, Zr) we find that conductance across the film is intimately related to the periodic table group of the substituent atom relative to Cu.

3‐D woven rectangular hollow structure conformal bearing microstrip antenna with different heights: Design, preparation, performance, and simulation

AbstractTraditional microstrip antennas have problems with heavy weight and poor gain. In order to reduce the weight of the antenna itself and improve its gain, the preforms of the 3‐D woven rectangular hollow structure conformal bearing microstrip antenna (3DWRHS‐CB‐MA)with different heights were woven from ultra‐high molecular weight polyethylene (UHMWPE) filament yarns and copper wires on a common loom through reasonable design. The preform was used as the reinforcement and epoxy resin was used as the matrix, four different heights (2, 4, 6, and 8 mm) of 3DWRHS‐CB‐MA were prepared by vacuum‐assisted resin transfer molding (VARTM) process. Finally, the electromagnetic performance was analyzed by high‐frequency structure simulator (HFSS) and experimental testing. The results showed that the frequency deviation of the 2 mm height microstrip antenna was minimal; while the 4 mm height microstrip antenna had better gain efficiency and directional diagram compared to others. The 4 mm height microstrip antenna has good radiation performance with a weight of only 35 g which shows that 3DWRHS‐CB‐MA are potential candidates for future intelligent textile materials and wireless communication fields.Highlights Weaving with UHMWPE filament yarns and copper wires on common looms. The preform was used as the reinforcement, and epoxy resin was used as the matrix. Simulation of electromagnetic characteristics of antennas using HFSS software. Proving the effectiveness of the electromagnetic simulation model. Revealing the electromagnetic radiation mechanisms.

Unprecedented electrical performance of friction-extruded copper-graphene composites

Copper-graphene composites show remarkable electrical performance surpassing traditional copper conductors albeit at a micron scale; there are several challenges in demonstrating similar performance at the bulk scale. In this study, we used shear assisted processing and extrusion (ShAPE) to synthesize macro-scale copper-graphene composites with a simultaneously lower temperature coefficient of resistance (TCR) and improved electrical conductivity over copper-only samples. We showed that the addition of 18 ppm of graphene decreased the TCR of C11000 alloy by nearly 11 %. A suite of characterization tools involving scanning and transmission electron microscopy along with atom probe tomography were used to characterize the grain size, crystallographic orientation, structure, and composition of copper grains and graphene additives in the feedstock and processed samples. We posit that the shear extrusion process may have transformed some of the feedstock graphene additives into higher defect-density agglomerates while retaining the structure of others as mono-to-tri-layer flakes with lower defect density. The combination of these additives with heterogeneous structures may have been responsible for the simultaneous decrease in TCR and enhanced electrical conductivity of the copper-graphene ShAPE composites.

Thixotropy and printability study of intense pulsed light sinterable copper paste formulations for flexible substrates

At present, most of the reported articles on IPL sintering of flexible copper paste focus mainly on the effects of IPL sintering parameters and copper powder modification methods on conductive copper patterns, which ignores the influence of thixotropy, printing and other properties that are of great concern in industrial production on the conductive copper pattern. In this article, four resin materials with distinctive mechanical properties, heat resistance, and stability are selected to develop a flexible copper paste formulation for IPL sintering. By focusing on the thixotropy and printing properties of different flexible copper pastes formulations, we found the relationship between these two properties and the performance of conductive copper patterns. The results show that thixotropy property affects the printing property, and the printing property affects the density and boundary definition of the conductive copper pattern film layer after sintering, thus affecting the conductivity. Finally, we obtained a flexible copper paste formulation suitable for IPL sintering with a printed line width of 35.47 μm, a line space of 31.55 μm, and a square resistance of 15.7 mΩ/◻.

IMPLEMENTATION OF DIPOLE ANTENNA WITH SQUARE REFLECTOR

This research is about how to develop a signal receiving antenna by using a tin can as a reflector and a ½ Lambda Dipole-shaped copper wire as a driver. With a direct experimental method to the research location which is useful for analyzing each signal strength captured. One of the objectives of this research is to support the improvement of the creative economy in Sungai Kupah Village, which still has inadequate signal quality. The results of this study indicate that only by using a tin can antenna can improve the quality of GSM signals. There are 2 providers used, namely Tri and Telkomsel by taking variable values of Signal Strength, RSSI, SINR, RSRP, RSRQ and taking daily data for 5 days of research in the morning and evening which aims to analyze what changes in value there are. variable data. The average value obtained by Provider Telkomsel for 5 days in the morning is Signal Strength -108.8 dBm, RSSI -78.62 dBm, SINR 3.78 dB, RSRP -108.8 dBm, RSRQ -12.1 dB, Ping 103.83 ms, Upload 60.21 Mbps, Download 9.92 Mbps. The average value obtained by Telkomsel Provider for 5 days afternoon is Signal Strength -116 dBm, RSSI -85.74 dBm, SINR 1.8 dB, RSRP -116 dBm, RSRQ -11.3 dB, Ping 156.33 ms, Upload 78.84 Mbps, Download 11.64Mbps. The average value obtained by Provider Tri for 5 days in the morning is Signal Strength -112.2 dBm, RSSI -85.42 dBm, SINR 5.88 dB, RSRP -122.2 dBm, RSRQ -9.3 dB, Ping 130.94 ms, Upload 50.84 Mbps, Download 8, 05Mbps. The average value obtained by Provider Tri for 5 days afternoon is Signal Strength -111.2 dBm, RSSI -84.34 dBm, SINR 6.62 dB, RSRP -111.2 dBm, RSRQ 9.9 dB, Ping 91.94 ms, Upload 14.60 Mbps.

Experimental and Modelling of Lightning Damage to Carbon Fibre-Reinforced Composites under Swept Stroke

Lightning swept stroke creates multiple lightning attachments along an aircraft in flight. This introduces distinct structural damage compared to that from a single-point lightning current injection test in laboratory. This study presents both experimental and numerical studies on lightning damage in carbon fibre-reinforced polymer (CFRP) composites under swept stroke. Coupled electrical–thermal finite element (FE) models were proposed to predict lightning damage to CFRP composites under single-point current injection and swept stroke, respectively. A lightning swept stroke testing method was proposed by embedding a copper wire inside the composites to simulate multiple lightning attachments on the composites. The FE-predicted damage from single-point current injection and swept stroke were comparable to those obtained from the experiments with a deviation less than 23%, demonstrating the effectiveness of the proposed FE model. Finally, the FE model was further utilised to gain insights into the failure mechanism of CFRP composites under swept stroke associated with different skip distances and peak currents. This paper provides an experimental method and a FE model for obtaining the LS damage of CFRP composite by swept stroke.

Creep failure analysis of crimp joints in aluminium and copper windings of distribution transformers

The present work investigates creep performance and contact resistance of Distribution Transformers (DTs) winding crimp joints under the influence of temperature and stress, aiming to reduce the failure rate of DTs. The integrity of crimp joints is crucial, as the field study revealed that a majority of crimp joints become unstable and show elevated contact resistance due to service exposure. These changes affect the steady-state creep rate of the crimp joint and the surrounding winding conductors, ultimately diminishing the operational lifespan of DTs. For experimentation, crimp joints with varying crimp points were fabricated for a 25 kVA DT using aluminium and copper conductors with diameters of 0.83 mm and 0.6 mm, respectively. For all types of joints i.e., Al-Al, Al-Cu and Cu-Cu, the 2-point crimp joint was identified as optimum in terms of tensile strength and contact resistance. The creep tests for the crimp joints were conducted under varying temperatures of 100 °C and 140 °C with stress levels of 40 MPa and 55 MPa as per ASTM E139-11. The steady-state creep rate and contact resistance of Al-Al crimp joints increased with an increase in temperature and stress. The creep life of DTs due to Al-Al and Al-Cu crimp joints is significantly less than the designed life of a typical DT. On the other hand, creep behaviour of copper winding crimp joints supports a significantly higher DT creep life even at a higher temperature of 140 °C and elevated stress of 55 MPa.

Laser-induced selective metallization of epoxy resin: Preparing ultra-thin and ultra-light motors

Epoxy composites with an excellent laser-induced selective metallization (LISM) capability were designed and prepared by combining the bisphenol A-type epoxy resin (EP) with laser sensitizers (CuO·Cr2O3 and ATO). The dispersion of laser sensitizers in epoxy molding compound (EMC), as well as their influence on the curing reaction and mechanical strength of epoxy composites, was investigated. We confirmed that CuO·Cr2O3 is the more suitable laser sensitizer for epoxy composites. The tensile strength of EP/CuO·Cr2O3 composite was 51.6 MPa, and the resistance of the obtained copper layers was 0.2 Ω. Moreover, this composite can be used to produce ultrafine copper wires and perforated circuits using LISM technology. Inspired by its excellent LISM performance, an ultra-thin and ultra-light motor was designed and fabricated. The weight of the entire motor was only 28.8 g and a thickness of 6 mm due to the integration of the stator frame and stator windings.

The impact of the combination of xanthan gum and polyvinyl pyrrolidone (PVP) on the chemical mechanical polishing of through silicon via (TSV) barrier layer

The material of the through silicon via (TSV) barrier layer is thicker than the barrier layer for copper wiring. In the chemical mechanical polishing (CMP) process, it is required to maintain a high removal rate of the tantalum (Ta) barrier layer and a low surface roughness and non-uniformity. To meet this technological challenge, the effect of a novel surfactant, xanthan gum, and polyvinylpyrrolidone (PVP) complex on the polishing performance and stability of the TSV barrier layer slurry under the conditions of pH 9, SiO2 concentration of 10 wt%, H2O2 concentration of 0.3 wt%, guanidine phosphate concentration of 1.5 wt%, and benzotriazole (BTA) concentration of 0.3 wt% was studied. The synergistic mechanism of xanthan gum and PVP was analyzed by electrochemical, X-ray photoelectron spectroscopy (XPS), and contact angle tests. The surface quality of Ta and copper (Cu) after polishing under different conditions was compared using atomic force microscopy (AFM). The experiment showed that when 0.025 wt% xanthan gum and 0.025 wt% PVP were added to the slurry, the removal rates of Ta and Cu were 109 nm/min and 51 nm/min respectively, and the surface non-uniformity was 2% and 1.9% respectively. At this time, the surface roughness Sq and Ra of Ta were 0.191 nm and 0.0215 nm respectively, and the surface roughness Sq and Ra of Cu were 0.344 nm and 0.0349 nm respectively, indicating that the slurry compounded with xanthan gum and PVP can maintain a high Ta removal rate while obtaining a high surface quality.

Evaluation of Copper and Gold Wire Bonds in PEM Devices

Abstract The shift from gold to copper wire bonds used in plastic encapsulated microcircuits (PEMs) has been gradual for the last few years. Many agencies and critics question the long-term robustness and reliability of copper wire bonds; however, PEM manufacturers have been thoroughly evaluating and optimizing the copper wire bond process over the last few years to produce highly reliable products. When the manufacturing process is optimized and closely controlled and monitored, copper wire bonds can be a reliable and stronger alternate to gold wire bonds. This paper details a copper wire bond study that specifically compares copper wire against gold wire bonds following combined environmental life stress test conditions. In this study, bond pull testing indicates good performance of both copper and gold wire bonds. The methods used in this analysis (destructive physical analysis, wire pull testing, and environmental testing) were effective techniques for evaluation of bond wire integrity, detection of manufacturing defects, and overall assessment of copper and gold wire bond processes. Based on wire bond testing in this analysis, the reliability and integrity of optimally developed copper wire bonds appear to be superior to or even stronger than gold wires in the same package type. Equivalent reliability was demonstrated for both copper and gold wire bonds in this test.

Design and investigation of losses of a low-current HTS AC cable for a promising cryogenic generation system

Currently, there are a large number of projects dedicated to electric machines aimed at use in the field of transport and equipped with windings made of high-temperature superconductors (HTS). These machines in their majority have rated currents significantly less than 1kA, which is a too low value for AC HTS cables in the power industry, where current values can reach up to 10kA. On the other hand, connecting, for example, an electric generator with cryogenic cooling and its load (which, most likely, will also have cryogenic cooling) with copper wires on board of a vehicle does not look like an effective solution. This article is devoted to the development of the concept of an alternating current transmission system for machines with a rated current of less than 1 kA through HTS cable. In order to achieve a compact design, it was decided to use a cable consisting of stacks of second-generation (2G) HTS tapes. A series of experiments was carried out with different numbers of tapes and directions of current in them for stacks of 2, 4 and 6 the HTS tapes. The results were compared with finite element modeling. The article shows that when current flows in adjacent cable HTS tapes in opposite directions, like as in bifilar windings, it is possible to achieve a significantly lower level of losses per tape than when current flows in the cable tapes in one direction.

Development of spiral square coils for magnetic labelling detection in microfluidic systems

Due to the development of microfluidic systems biomedical microelectromechanical systems (BioMEMS) for magnetic labelling detection by magnetic microbeads circling in microfluidic channels, we used the magnetic field created by microcoils. The magnetic field associated with the electric current, but with negatively affects if its value increases too much. Handling bio-species in the microfluidic chip requires that the temperature maintained to keep the cells to prevent their destruction. In this paper we have described the spiral square coil design of different structures to produce an effective magnetic flux density. The simulation of the magnetic flux density is carried out with the help of the COMSOL software. We have presented an optimization of the geometric parameters of the microcoil for a better performance and a miniaturization of the structure with copper wire section S=25 µm<sup>2</sup> and inter-wire space a=5 µm. We have also developed this microcoil by adding a ferromagnetic core to the inner center, the results obtained in this work shown that the magnetic flux density increases around 1.07 times in Bx and 1.45 times in Bz. This new approach in designing a microcoil allows to obtaining a fast trapping of the microbeads and a highly sensitive biological element detection and avoiding increase heat ratio in microfluidic systems.

Characterization of magnetic field for loading, trapping and transferring cold atom close to the atom chip’s surface

Atom chips provide flexible technologies for implementing modern concepts in quantum optics, quantum measurement, and quantum information processing. Atom chips are miniature devices that confine, control and manipulate cold atoms using electric, magnetic, and light fields. Due to the shrinkage of scale, arbitrary magnetic traps can be generated from current sources outside the chip’s vacuum compartment, in contrast to a traditional setup. This makes it easy to change trap configurations in an experiment that involves rapid prototyping of quantum states and quantum trajectory designs in free space. In this work, we show relevant parameters needed for transferring a cold atom cloud at the recoil limit from a magneto-optical trap (MOT) to an area close to the atom chip. To create a movable magnetic potential for this transfer, we used the MOT coils and an additional pair of coils in an anti-Helmholtz configuration. The properties of the movable potential were obtained by performing the Computer Simulation Tool (CST EM Studio suite®). Furthermore, an appropriate magnetic trap on a chip is developed, based on the simulation from COMSOL Multiphysics. We used a magnetic field gradient of around 20 G/cm to transport the cold atom with a distance over 20 mm with a temperature gain below 100 micro-Kelvin. The simulation results are based on an atom chip with a size of 2×2 cm2 and a copper wire thickness of 2 mm. The atom chip consists of Z, U and I-shaped wires that generate a quadrupole magnetic field. The resulting field minimum can be made at least 7 mm away from the chip surface.

ТАЛШЫҚТЫ-ОПТИКАЛЫҚ БАЙЛАНЫС ЖОЛДАРЫ НЕГІЗІНДЕ ЭНЕРГИЯ ТАРАТУ ЖҮЙЕСІНІҢ ЗЕРТХАНАЛЫҚ ҮЛГІСІН ӘЗІРЛЕУ ЖӘНЕ ЗЕРТТЕУ

In this article, a laboratory sample of an energy transmission system over a fiber-optic communication line is being developed and investigated, which makes it possible to provide power to autonomous ultra-low-power electronic devices located at a considerable distance from energy sources. The system being developed will make it possible to abandon the use of copper conductors and batteries for autonomous stationary devices, which is associated with certain difficulties from the point of view of technical implementation. The result of this study is a developed laboratory sample that allows measuring the values of current and voltage in the branch of the photodetector. The method of an equivalent generator was used, as well as the well-known laws of a circuit with two dedicated nodes for an active two- pole. When analyzing the literature, scientific achievements and discoveries in the field of research, a proprietary research concept was formulated that differs from foreign analogues. During the experiment, the photodetector was in idle, short-circuit mode and was connected to a high-resistance load. Based on experimental data, volt-ampere characteristics (VAC) were constructed using a radiation source (laser) with a power of 10 and 30 MW. The technical parameters and characteristics of the radiation source and the irradiated silicon crystal are given. The output electrical power is determined using the laws of electrical engineering, including Ohm's law. To process the results obtained, quadratic interpolation of the function, the results of the root-mean-square approximation were used, and regression analysis was also performed. Absolute and relative errors were calculated. The student's coefficient was determined with a confidence interval of 0.95. According to the results of the study, the efficiency of a laboratory sample of an energy transmission system over a fiber-optic communication line was determined.

Picosecond laser writing of highly conductive copper micro-contacts from deep eutectic solvents

Picosecond laser writing of highly conductive copper micro-contacts from deep eutectic solvents