Search Results (2,665)

In this study, silicon carbide (SiC) thin films for resistive random-access memory (RRAM) devices were successfully prepared using the radio-frequency magnetron sputtering method at deposition powers of 50 and 75 W for 1 h. The aluminum (Al) top electrode of the RRAM devices was also fabricated using thermal evaporator deposition. Additionally, the electrical properties of the SiC thin film RRAM devices were determined using a B2902A mechanism. The current–voltage (I–V) curves of the as-deposited SiC thin films at 50 and 75 W power levels were measured and analyzed. Specifically, the set and reset voltages for the RRAM devices deposited at 50 and 75 W were approximately 1.2 and −1.5 V, respectively. For the annealed samples, the memory windows of the 75 W SiC thin film RRAM devices treated at 300 °C were found to be around 10⁵. Full article

Background: Parkinson’s disease (PD) in advanced stages becomes, over time, a significant challenge, as oral medication becomes ineffective, and it may become necessary to switch to device-assisted therapy (DAT). This should be personalized according to the stage of the disease, the cognitive status of the patients, the association of frailty syndrome or other comorbidities, the support in care from the family, etc. Levodopa–carbidopa–entacapone intestinal gel can significantly improve the status of patients, provided that they are correctly selected for this type of treatment. Materials and Methods: We conducted a single-center prospective study including 20 advanced PD patients, who received a levodopa–carbidopa–entacapone gel through an intestinal pump, within the Parkinson’s Disease Multimodal Treatment Center of the Neurology Clinic of the “St. Ap. Andrew” County Emergency Clinical Hospital in Galați, Romania. The evaluations were performed at baseline (T0), after intestinal pump insertion (T1), and 6 months after the procedure (T2). Results: In the study group, the administration of the levodopa–carbidopa–entacapone intestinal gel, using the device for intestinal administration, had significant benefits, especially for motor symptoms. The periods of off, no-on, freezing, sudden-off, as well as dyskinesia and morning akinesia, were significantly reduced. Among the non-motor symptoms, depression and sleep disorders improved, with no changes in cognitive status and psychotic disorders. Conclusions: Adding new data for the use of device-assisted therapy in advanced PD, our study also highlights the need to further research this challenging patient profile. Full article

In the era of artificial intelligence, neuromorphic devices that simulate brain functions have received increasingly widespread attention. In this paper, an artificial neural synapse device based on ZnAlSnO thin-film transistors was fabricated, and its electrical properties were tested: the current-switching ratio was 1.18 × 10⁷, the subthreshold oscillation was 1.48 V/decade, the mobility was 2.51 cm²V⁻¹s⁻¹, and the threshold voltage was −9.40 V. Stimulating artificial synaptic devices with optical signals has the advantages of fast response speed and good anti-interference ability. The basic biological synaptic characteristics of the devices were tested under 365 nm light stimulation, including excitatory postsynaptic current (EPSC), paired-pulse facilitation (PPF), short-term plasticity (STP), and long-term plasticity (LTP). This device shows good synaptic plasticity. In addition, by changing the gate voltage, the excitatory postsynaptic current of the device at different gate voltages was tested, two different logical operations of “AND” and “OR” were achieved, and the influence of different synaptic states on memory was simulated. This work verifies the application potential of the device in the integrated memory and computing architecture, which is of great significance for promoting the high-quality development of neuromorphic computing hardware. Full article

The white cane is a reliable and often-used assistive aid; however, it does not protect against obstacles at the head level. We designed and built an ultrasonic-based obstacle detector with a limited detection field in front of the head. The detector is located on the chest and can be mounted on backpack straps or around the neck. We have performed testing with 74 blind people and their instructors. Blind people used the device for three to four weeks in their regular lives, and instructors tested it by themselves or with their clients. The testing showed that individualization by the type of mounting is helpful. The needed detection distance depends on the situation and the speed of movement. In total, 70% of the users were satisfied with the distance options 80 cm, 110 cm, and 140 cm. 81% of the testers were satisfied, or somewhat satisfied, with the sliding switches to control. It is simple, and its position (setting) can be detected by touch. The testers see the benefit of using the device, especially in unknown environments (outdoor and indoor), primarily because of the increased safety by movement (64%) or the feeling of security (41%). Full article

In space applications, the required levels of performance and reliability drive up hardware costs. Reducing the efforts related to device development and validation may help balance the budget. A versatile transmitter for space telemetry is implemented here that may help in this respect. Such a device can switch across different linear and continuous phase modulation schemes just by modifying its parameters, while maintaining the same hardware structure. Results from an extensive campaign of experimental test measurements of the device are reported. A GNURadio-implemented receiver is developed to test performance of the actual transmitter by considering all the main blocks of the receiver chain and computing the bit error rate (BER) at the receiver. After testing different configurations, results confirm that the BER of the improved one-filter modulated signal is lower than the BER obtained using only the first Laurent decomposition component. Full article

Background and Objectives: Automated insulin delivery (AID) systems represent a major advancement in type 1 diabetes (T1D) management, particularly in pediatric populations. However, real-world evidence comparing their effectiveness to conventional multiple daily injection (MDI) therapy in youth remains limited. This study aimed to evaluate the impact of transitioning from MDI therapy to AID systems on glycemic control in children and adolescents with T1D, and to explore potential differences based on baseline HbA1c levels and device type. Materials and Methods: In this single-center, retrospective observational study, 76 children and adolescents with T1D were evaluated before and after switching from MDI to either the Medtronic MiniMed™ 780G or Tandem t:slim X2™ Control-IQ system. Glycemic control was assessed using continuous glucose monitoring (CGM)-derived metrics at three time points: the last 15 days of MDI therapy (T0), 15 days after (T1), and 6 months after (T2) AID initiation. Statistical comparisons were conducted across time points and between subgroups stratified by baseline HbA1c and AID system. Results: Significant improvements in glycemic control were observed as early as 15 days after AID initiation, with sustained benefits at 6 months. Time in range (TIR) increased from 62.0% at baseline to 76.7% at 15 days and 75.8% at 6 months, and time in tight range (TITR) from 39.8% to 53.9% at T1 and 52.1% at T2 (both p < 0.001). Improvements were more pronounced in participants with higher baseline HbA1c (+16.9% for TITR and +22.3% for TIR). No significant differences in glycemic outcomes were observed between device groups, although algorithm-driven differences in insulin delivery patterns were noted. Total daily insulin dose and BMI increased significantly over time (p < 0.001 and p = 0.008, respectively). Conclusions: AID therapy leads to rapid and sustained improvements in glycemic control among youth with T1D, particularly in those with suboptimal baseline control. These benefits highlight the clinical value of AID systems, while also emphasizing the need for monitoring potential metabolic impacts. Full article

Gallium oxide (Ga₂O₃)-based memristors are gaining traction as promising candidates for next-generation electronic devices toward in-memory computing, leveraging the unique properties of Ga₂O₃, such as its wide bandgap, high thermodynamic stability, and chemical stability. This review explores the evolution of memristor theory for Ga₂O₃-based materials, emphasising capacitive memristors and their ability to integrate resistive and capacitive switching mechanisms for multifunctional performance. We discussed the state-of-the-art fabrication methods, material engineering strategies, and the current challenges of Ga₂O₃-based memristors. The review also highlights the applications of these memristors in memory technologies, neuromorphic computing, and sensors, showcasing their potential to revolutionise emerging electronics. Special focus has been placed on the use of Ga₂O₃ in capacitive memristors, where their properties enable improved switching speed, endurance, and stability. In this paper we provide a comprehensive overview of the advancements in Ga₂O₃-based memristors and outline pathways for future research in this rapidly evolving field. Full article

This study presents a reconfigurable planar photonic device capable of dynamically switching between optical filter and absorber functionalities by exploiting the phase transition properties of GeTe, a chalcogenide phase-change material. The device adopts a Metal–Dielectric–PCM architecture composed of silver (Ag), silicon dioxide (SiO₂), and GeTe layers, each playing a distinct role: the silver layer governs the transmission and absorption efficiency, the SiO₂ layer controls the resonance conditions, and the GeTe layer determines the device’s scattering behavior via its tunable optical losses. Numerical simulations revealed that the structure enables high RGB transmission in the amorphous state and broadband absorption in the crystalline state. By adjusting geometric parameters—especially the metallic thickness—the device exhibits finely tunable spectral responses under varying polarizations and incidence angles. These findings highlight the synergistic interplay between material functionality and layer configuration, positioning this platform as a compact and energy-efficient solution for applications in tunable photonics, optical sensing, and programmable metasurfaces. Full article

Sol–gel-processed zinc oxide (ZnO) and magnesium-doped zinc oxide (ZnMgO) are widely used in quantum dot light-emitting diodes (QLEDs) due to their excellent charge transport properties, ease of fabrication, and tunable film characteristics. In particular, the ZnMgO/ZnO bilayer structure has attracted considerable attention for its dual functionality: defect passivation by ZnMgO and efficient charge transport by ZnO. However, while the effects of resistive switching (RS) in individual ZnO and ZnMgO layers on the aging behavior of QLEDs have been studied, the RS characteristics of sol–gel-processed ZnMgO/ZnO bilayers remain largely unexplored. In this study, we systematically analyzed RS properties of an indium tin oxide (ITO)/ZnMgO/ZnO/aluminum (Al) device, demonstrating superior performance compared to devices with single layers of either ZnMgO or ZnO. We also investigated the shelf-aging characteristics of RS devices with single and bilayer structures, finding that the bilayer structure exhibited the least variation over time, thereby confirming its enhanced uniformity and reliability. Furthermore, based on basic current–voltage measurements, we estimated accuracy variations in MNIST pattern recognition using a two-layer perceptron model. These results not only identify a promising RS device architecture based on the sol–gel process but also offer valuable insights into the aging behavior of QLEDs incorporating ZnMgO/ZnO bilayers, ITO, and Al electrodes. Full article

This study investigates the arc-induced degradation mechanisms of Ag–Ni (90/10) electrical contacts under controlled laboratory cycling conditions using a custom PLC-controlled switching system. The degradation process is characterized by three distinct wear stages: initial arc erosion with localized material removal, a restructuring phase marked by melting and material redistribution, and a final film deposition stage leading to topographical homogenization but functional degradation. Raman spectroscopy confirms progressive nickel oxide and carbonaceous contamination, correlating with contact resistance trends that exhibit multi-phase behavior. Subsurface analysis reveals critical structural damage at mid-life cycles, emphasizing the importance of preventive maintenance. The findings advance understanding of wear mechanisms in Ag–Ni contacts and provide insights into optimizing their service life in industrial switching applications. Full article

The magnetic properties of molecular nanomagnets can be finely modulated by light, which provides great potential in optical switches, smart sensors, and data storage devices. Light-induced spin transition, structure changes, and radical formation could tune the static and dynamic magnetic properties of molecular nanomagnets with high spatial and temporal resolutions. Herein, we summarize the design strategies of photoresponsive molecular nanomagnets and review the recent advances in transition metal/lanthanide molecular nanomagnets with photomagnetic properties. The photoresponsive mechanism based on spin transition, photocyclization, and photogenerated radicals is discussed in detail, providing insights into the photomagnetic properties of molecular nanomagnets for advanced photoresponsive materials. Full article

A physical unclonable function (PUF) leverages the unclonable random variations in device behavior due to defects incurred during manufacturing to produce a unique “biometric” that can be used for authentication. Here, we show that the threshold current for the switching of a magnetic tunnel junction via spin transfer torque is sensitive to the nature of structural defects introduced during manufacturing and hence can be the basis of a PUF. We use micromagnetic simulations to study the threshold currents for six different defect morphologies at two different temperatures to establish the viability of a PUF. We also derive the challenge–response set at the two different temperatures to calculate the inter- and intra-Hamming distances for a given challenge. Full article

The most widely used nanowire channel architecture for creating state-of-the-art high-performance transistors is the nanowire wrap-gate transistor, which offers low power consumption, high carrier mobility, large electrostatic control, and high-speed switching. The frequency-dependent capacitance and conductance measurements of triangular-shaped GaN nanowire wrap-gate transistors are measured in the frequency range of 1 kHz–1 MHz at room temperature to investigate carrier trapping effects in the core and at the surface. The performance of such a low-dimensional device is greatly influenced by its surface traps. With increasing applied frequency, the calculated trap density promptly decreases, from 1.01 × 10¹³ cm⁻² eV⁻¹ at 1 kHz to 8.56 × 10¹² cm⁻²eV⁻¹ at 1 MHz, respectively. The 1/f-noise features show that the noise spectral density rises with applied gate bias and shows 1/f-noise behavior in the accumulation regime. The fabricated device is controlled by 1/f-noise at lower frequencies and 1/f²-noise at frequencies greater than ~ 0.2 kHz in the surface depletion regime. Further generation–recombination (G-R) is responsible for the 1/f²-noise characteristics. This process is primarily brought on by electron trapping and detrapping via deep traps situated on the nanowire’s surface depletion regime. When the device works in the deep-subthreshold regime, the cut-off frequency for the 1/f²-noise characteristics further drops to a lower frequency of 30 Hz–10⁴ Hz. Full article

As a common signal sensing device in pulsed eddy current detection, coil sensors often have parameter offset problems in practical applications. The error in the receiving coil parameters will have a great impact on the early signal. In order to ensure the accuracy of the early signal, this paper first analyzes the response characteristics of the receiving coil and the influence of the coil parameters on the accuracy of signal deconvolution and establishes the mathematical relationship between the response signal and the characteristic parameters, and between the characteristic parameters and the receiving coil parameters under active underdamped oscillation. Subsequently, the parameter feature extraction errors under different state switching capacitors were compared through simulation analysis, the state switching capacitor value was determined, and the receiving coil parameter solution method based on the Levenberg–Marquardt (LM) algorithm was determined based on the parameter feature extraction results. The experimental results demonstrate that the proposed method achieves a capacitance estimation error of just 0.0159% and an inductance error of 0.158%, effectively minimizing early signal distortion and enabling precise identification of receiving coil parameters. Full article

With the widespread application of multilevel inverters, device losses have become a critical area of research. A key limitation of conventional three-level discontinuous pulse width modulation (DPWM) strategies is their inability to maintain switching device clamping during the peak intervals of the load current, especially under varying load power factor conditions, thereby reducing switching losses. This paper proposes an improved three-level power factor adaptive DPWM (PFA-DPWM) strategy that minimizes switching losses by clamping the power devices during the one-third fundamental period of maximum load current. First, a unified mathematical model of DPWM strategies is established. Theoretical analysis demonstrates that phase disposition (PD) carrier modulation for three-level inverter exhibits superior line voltage harmonic characteristics. Based on this, a theoretical comparison of switching losses and harmonic distortion for various DPWM schemes is conducted. The proposed PFA-DPWM control strategy has the minimum switching loss without compromising harmonic performance. The efficacy and validity of the proposed strategy are confirmed by comprehensive simulation and experimental results. Full article