Search Results (99)

Neuromorphic computing, inspired by the human brain’s architecture, offers a transformative approach to overcoming the limitations of traditional von Neumann systems by enabling highly parallel, energy-efficient information processing. Among emerging materials, MXenes—a class of two-dimensional transition metal carbides and nitrides—have garnered significant attention due to their exceptional electrical conductivity, tunable surface chemistry, and mechanical flexibility. This review comprehensively examines recent advancements in MXene-based optoelectronic synapses and neurons, focusing on their structural properties, device architectures, and operational mechanisms. We emphasize synergistic electrical–optical modulation in memristive and transistor-based synaptic devices, enabling improved energy efficiency, multilevel plasticity, and fast response times. In parallel, MXene-enabled optoelectronic neurons demonstrate integrate-and-fire dynamics and spatiotemporal information integration crucial for biologically inspired neural computations. Furthermore, this review explores innovative neuromorphic hardware platforms that leverage multifunctional MXene devices to achieve programmable synaptic–neuronal switching, enhancing computational flexibility and scalability. Despite these promising developments, challenges remain in device stability, reproducibility, and large-scale integration. Addressing these gaps through advanced synthesis, defect engineering, and architectural innovation will be pivotal for realizing practical, low-power optoelectronic neuromorphic systems. This review thus provides a critical roadmap for advancing MXene-based materials and devices toward next-generation intelligent computing and adaptive sensory applications. 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

In response to escalating global energy demands and environmental challenges, electrochromic (EC) smart windows have emerged as a transformative technology for adaptive solar modulation. Herein, we report the rational design and fabrication of a bilayer WO₃/TiO₂ heterostructure via a synergistic two-step strategy involving the electrochemical deposition of amorphous WO₃ and the controlled hydrothermal crystallization of TiO₂. Structural and morphological analyses confirm the formation of phase-pure heterostructures with a tunable TiO₂ crystallinity governed by reaction time. The optimized WTi-5 configuration exhibits a hierarchically organized nanostructure that couples the fast ion intercalation dynamics of amorphous WO₃ with the interfacial stability and electrochemical modulation capability of crystalline TiO₂. Electrochromic characterization reveals pronounced redox activity, a high charge reversibility (98.48%), and superior coloration efficiency (128.93 cm²/C). Optical analysis confirms an exceptional transmittance modulation (ΔT = 82.16% at 600 nm) and rapid switching kinetics (coloration/bleaching times of 15.4 s and 6.2 s, respectively). A large-area EC device constructed with the WTi-5 electrode delivers durable performance, with only a 3.13% degradation over extended cycling. This study establishes interface-engineered WO₃/TiO₂ bilayers as a scalable platform for next-generation smart windows, highlighting the pivotal role of a heterostructure design in uniting a high contrast, speed, and longevity within a single EC architecture. Full article

Photoelectrochromic devices, which combine light-induced color change with energy-efficient optical modulation, have attracted significant attention for applications such as smart windows, displays, and optical sensors. However, achieving high optical modulation, fast switching speeds, and long-term stability remains a major challenge. In this study, we explore the structural and photoelectrochromic enhancements in tungsten oxide (WO₃) films achieved by doping with molybdenum disulfide quantum dots (MoS₂ QDs) and grapheneoxide–molybdenum disulfide quantum dots (GO–MoS₂ QDs) for advanced photoelectrochromic devices. X-ray diffraction (XRD) analysis revealed that doping with MoS₂ QDs and GO–MoS₂ QDs leads to a reduction in the crystallite size of WO₃, as evidenced by the broadening and decrease in peak intensity. Transmission Electron Microscopy (TEM) confirmed the presence of characteristic lattice fringes with interplanar spacings of 0.36 nm, 0.43 nm, and 0.34 nm, corresponding to the planes of WO₃, MoS₂, and graphene. Energy-Dispersive X-ray Spectroscopy (EDS) mapping indicated a uniform distribution of tungsten, oxygen, molybdenum, and sulfur, suggesting homogeneous doping throughout the WO₃ matrix. Scanning Electron Microscopy (SEM) analysis showed a significant decrease in film thickness from 724.3 nm for pure WO₃ to 578.8 nm for MoS₂ QD-doped WO₃ and 588.7 nm for GO–MoS₂ QD-doped WO₃, attributed to enhanced packing density and structural reorganization. These structural modifications are expected to enhance photoelectrochromic performance by improving charge transport and mechanical stability. Photoelectrochromic performance analysis showed a significant improvement in optical modulation upon incorporating MoS₂ QDs and GO–MoS₂ QDs into the WO₃ matrix, achieving a coloration depth of 56.69% and 70.28% at 630 nm, respectively, within 10 min of 1.5 AM sun illumination, with more than 90% recovery of the initial transmittance within 7 h in dark conditions. Additionally, device stability was improved by the incorporation of GO–MoS₂ QDs into the WO₃ layer. The findings demonstrate that incorporating MoS₂ QDs and GO–MoS₂ QDs effectively modifies the structural properties of WO₃, making it a promising material for high-performance photoelectrochromic applications. Full article

Objectives: To evaluate the efficacy of faricimab in patients with neovascular age-related macular degeneration (nAMD) that did not respond to other VEGF inhibitors. Methods: This retrospective study included the eyes of patients diagnosed with nAMD who had been switched to faricimab treatment due to the persistence of intraretinal fluid (IRF) and/or subretinal fluid (SRF), despite monthly anti-VEGF treatment with aflibercept, bevacizumab, or ranibizumab using the treat and extend regimen, and who had received at least three faricimab injections following the switch. Best-corrected visual acuity (BCVA) measurement and optical coherence tomography (OCT) analysis were performed at each visit, and the OCT results were graded by two independent readers. Results: We included 41 eyes of 39 patients (21 male, 18 female) with a mean age of 80.5 ± 8.1 years. The median duration of anti-VEGF treatment prior to the switch to faricimab was 5.0 years, with a median of 53 injections. Complete resolution of IRF and SRF was observed after the first dose of faricimab in 12 eyes (29.3%) and after the third dose in 15 eyes (36.6%). Twenty-eight eyes reached a follow-up time after a switch of at least 12 months, with a median of 10 faricimab injections. Of these 28 eyes, 10 eyes (35.7%) exhibited complete IRF/SRF resolution; treatment intervals were extended beyond 4 weeks in 21 eyes (80.7%), and 8 eyes (28.6%) presented complete IRF/SRF resolution under extended treatment intervals at month 12. Central retinal thickness after 12 months was reduced from a median of 368.0 µm to 297.5 µm (p < 0.001), and the BCVA remained stable (p = 0.057). No adverse events were reported throughout the entire treatment period. Conclusions: In nAMD patients with poor anti-VEGF treatment response, complete and fast fluid resolution and the extension of treatment intervals can be reached by switching to faricimab, even after years of prior unsuccessful therapy. Full article

In this paper, we present the analysis of functional alloy samples containing metals aluminum (Al), copper (Cu), lead (Pb), silicon (Si), tin (Sn), and zinc (Zn) using a Q-switched Nd laser operating at a wavelength of 532 nm with a pulse duration of 5 ns. Nine pelletized alloy samples were prepared, each containing varying chemical concentrations (wt.%) of Al, Cu, Pb, Si, Sn, and Zn—elements commonly used in electrotechnical and thermal functional materials. The laser beam is focused on the target surface, and the resulting emission spectrum is captured within the temperature interval of $9.0\times {10}^3$ to $1.1\times {10}^4$ K using a set of compact Avantes spectrometers. Each spectrometer is equipped with a linear charged-coupled device (CCD) array set at a 2 μs gate delay for spectrum recording. The quantitative analysis was performed using calibration-free laser-induced breakdown spectroscopy (CF-LIBS) under the assumptions of optically thin plasma and self-absorption-free conditions, as well as local thermodynamic equilibrium (LTE). The net normalized integrated intensities of the selected emission lines were utilized for the analysis. The intensities were normalized by dividing the net integrated intensity of each line by that of the aluminum emission line (Al II) at 281.62 nm. The results obtained using CF-LIBS were compared with those from the laser ablation time-of-flight mass spectrometer (LA-TOF-MS), showing good agreement between the two techniques. Furthermore, a random forest technique (RFT) was employed using LIBS spectral data for sample classification. The RFT technique achieves the highest accuracy of ~98.89% using out-of-bag (OOB) estimation for grouping, while a 10-fold cross-validation technique, implemented for comparison, yields a mean accuracy of ~99.12%. The integrated use of LIBS, LA-TOF-MS, and machine learning (e.g., RFT) enables fast, preparation-free analysis and classification of functional metallic materials, highlighting the synergy between quantitative techniques and data-driven methods. Full article

Viewing high-redshift sources at near-opposite directions on the sky can ensure, using light-travel-time arguments, acausality between their emitted photons. One utility would be true random-number generation through sensing these via two independent telescopes that each flip a switch based on the latest-arrived colours; for example, to autonomously control a quantum-mechanical (QM) experiment. Although demonstrated with distant quasars, those were not fully acausal pairs, which are restricted when simultaneously viewed from the ground at any single observatory. In optical light, such faint sources also require a large telescope aperture to avoid sampling assumptions when imaged at fast camera framerates: unsensed intrinsic correlations between them or equivalently correlated noise may ruin the expectation of pure randomness. One such case that could spoil a QM test is considered. Based on that, the allowed geometries and instrumental limits are modelled for any two ground-based sites, and their data are simulated. For comparison, an analysis of photometry from the Gemini twin 8 m telescopes is presented using the archival data of well-separated bright stars obtained with the instruments ‘Alopeke (on Gemini North in Hawai’i) and Zorro (on Gemini-South in Chile) simultaneously in two bands (centred at $562\mathrm{nm}$ and $832\mathrm{nm}$) with 17 Hz framerate. No flux correlation is found; these results were used to calibrate an analytic model predicting where a search with a signal-to-noise over 50 at 50 Hz can be made using the same instrumentation. Finally, the software PDQ (Predict Different Quasars) is presented, which searches a large catalogue of known quasars, reporting those with a brightness and visibility suitable to verify acausal, uncorrelated photons at these limits. Full article

WO₃ electrochromic films have emerged as potential candidates for smart windows due to their cost-effectiveness, fast switching speed, and strong chemical stability. However, the inherent contradiction between the high coloring efficiency of amorphous WO₃ and the cycling durability of crystalline WO₃ remains a critical challenge in practical applications. This study proposes an innovative heterostructure engineering strategy, achieving precise control of the amorphous/crystalline bilayer WO₃ heterointerface (148 nm a-WO₃/115 nm c-WO₃) for the first time through phase boundary regulation, using well-controlled magnetron sputtering and post-deposition thermal annealing processes. Multimodal characterization using XRD, XPS, and SEM indicates that the heterointerface optimizes performance through a dynamic charge transfer mechanism and structural synergistic effects: the optimized bilayer structure achieves 76.57% optical modulation (at 630 nm) under −1.0 V and maintains a ΔT retention rate of 45.02% after 600 cycles, significantly outperforming single amorphous (8.34%) and crystalline films (14.34%). XPS analysis reveals a dynamic equilibrium mechanism involving W⁵⁺/Li⁺ at the interface, and the Li⁺ diffusion coefficient (D₀ = 4.29 × 10⁻¹⁰ cm²/s) confirms that the amorphous layer dominates rapid ion transport, while the crystalline matrix enhances structural stability through its ordered crystalline structure. This study offers a new paradigm for balancing the efficiency and longevity of electrochromic devices, with the compatibility of magnetic sputtering promoting the industrialization process of large-area smart windows. Full article

In complex electromagnetic environments, such as substations, converter stations in power systems, and the compartments of aircraft, trains, and automobiles, electromagnetic immunity testing is crucial. It requires that the electric field sensor has features such as a large dynamic measurement range (amplitude from hundreds of V/m to tens of kV/m), a fast response speed (response time in the order of nanoseconds or sub-nanoseconds), a wide test bandwidth (DC to 1 GHz even above), miniaturization, and robustness to strong electromagnetic interference. This paper introduces a multi-channel, ultra-wideband transient electric field measurement system. The system’s analog bandwidth covers the spectrum from DC and a power frequency of 50 Hz to partial discharge signals, from DC to 1.65 GHz, with a storage depth of 2 GB (expandable). It overcomes issues related to the instability, insufficient bandwidth, and lack of accuracy of optical fibers in analog signal transmission by using front-end digital sampling based on field-programmable gate array (FPGA) technology and transmitting digital signals via optical fibers. This approach is effectively applicable to measurements in strong electromagnetic environments. Additionally, the system can simultaneously access four channels of signals, with synchronization timing reaching 300 picoseconds, can be connected to voltage and current sensors simultaneously, and the front-end sensor can be flexibly replaced. The performance of the system is verified by means of a disconnect switch operation and steady state test in an HVDC converter station. It is effectively applicable in scenarios such as the online monitoring of transient electromagnetic environments in high-voltage power equipment, fault diagnosis, and the precise localization of radiation sources such as partial discharge or intentional electromagnetic interference (IEMI). Full article

The switching properties of nematic liquid crystals under electrical and mechanical stresses play a fundamental role in the design and fabrication of electro-optical devices. Depending on the stress applied to a nematic texture confined in a pi-cell, different nematic configurations are allowed inside the cell, while the induced distortion is relaxed by means of growing biaxial domains which can end with the order reconstruction phenomenon, a transition connecting two topologically different nematic textures which can occur in different regions of the pi-cell. Due to the different space and time scales involved, modelling in the frame of the Landau–de Gennes order tensor theory is mandatory to correctly describe the fast-switching mechanisms involved, while from a computational point of view, sophisticated numerical techniques are required to grasp tiny and fast features which can be predicted by the mathematical modelling. In this paper, we review the results obtained from the mathematical and numerical modelling of a 5CB liquid crystal confined in a pi-cell performed by using a numerical technique based on the equidistribution principle, tailored for the description of a complex physical system in which fast switching phenomena are coupled with strong distortions. After a recap on the underneath theory and on the numerical method, we focus on the switching properties of the nematic material when subjected to variable mechanical and electrical stresses in both symmetric and asymmetric conditions. Full article

In this article, a series of novel conducting copolymers P(FuPy-co-EDOT) are prepared via cyclic voltammetry electropolymerization method by using N-furfuryl pyrrole (FuPy) and 3,4-ethylenedioxythiophene (EDOT) as comonomers. The molecular structure, surface morphology, electrochemical, and optical properties of the resulting copolymers are characterized in detail upon varying the feed ratios of FuPy/EDOT in the range of 1/1 to 1/9. The results demonstrate that the prepared P(FuPy-co-EDOT) copolymers with a higher proportion of EDOT units (FuPy/EDOT: 2/8~1/9) possess good redox activity, tunable optical absorption performances, and low band gaps (1.75~1.86 eV). Spectroelectrochemistry studies indicate that the resulting copolymers with increased EDOT units show strengthened electrochromic characteristics, exhibiting a red-to-green-to-blue multicolor reversible transition, especially for the P(FuPy₁-co-EDOT₉) copolymer films. They also show increased optical contrast (9~34%), fast response time (0.8~2.4 s), and good coloring efficiency (110~362 cm² C⁻¹). Additionally, the complementary bilayer P(FuPy-co-EDOT)/PEDOT electrochromic devices (ECDs) are also assembled and evaluated to hold excellent electrochromic switching performances with relatively high optical contrast (25%), rapid response time (0.9 s), and satisfactory coloring efficiency (416 cm² C⁻¹). Together with the superior open circuit memory and cycling stability, they can be used as a new type of electrochromic material and have considerable prospects as promising candidates for electrochromic devices. Full article

Phenoxazine, as an organic-small-molecule chromophore, has attracted much attention for its potential electrochromic applications recently. To develop appealing materials, phenoxazine chromophores were introduced at the N-position of carbazole–thiophene pigment, yielding two novel monomers (DTCP and DDCP), whose chemical structures were characterized by NMR, HRMS and FTIR. The results of the optical property study indicate that little influence could be observed in the presence of the phenoxazine chromophore. Corresponding polymer films on the surface of an ITO/glass electrode were obtained through electropolymerization. The electrochemical features displayed were various due to the introduction of the phenoxazine group. The spectroelectrochemical results demonstrate that the color of the polymer films could be changed. Compared with the PDDC films, the PDDCP films exhibited three different colors (tangerine, green and purple colors) in different redox states, which could be attributed to the synergistic effect between the carbazole–thiophene conjugate chain and the phenoxazine group. Moreover, fast switching time could be seen due to the presence of the phenoxazine chromophore. This study could provide a reference for obtaining high-performance electrochromic materials. Full article

Graphene oxide (GO) and reduced graphene oxide (rGO) have emerged as robust materials in the development of SAs for erbium-doped fiber lasers (EDFLs). Their exceptional optical properties, such as broadband absorption and fast recovery times, make them ideal candidates for achieving ultrashort pulse operation in EDFLs. With its higher oxygen content, GO offers greater nonlinearity and a tunable absorption spectrum, while rGO, yielded through chemical reduction, exhibits enhanced electrical conductivity and higher saturable absorption. These properties facilitate the generation of ultrashort pulses in EDFLs, which are highly desired for various medical imaging, telecommunications, and material processing applications. This review paper comprehensively analyzes the advancements in GO and rGO SAs in the context of EDFLs for mode-locking and Q-switching applications. The performance of EDFLs utilizing GO and rGO SAs is critically evaluated, focusing on key parameters, such as modulation depth, pulse duration, repetition rate, average power, pulse energy, peak power, and signal-to-noise ratio. Additionally, this review delves into the various synthesis methods of GO and rGO thin film, highlighting their impact on the optical properties and performance of SAs. The discussion on techniques to integrate the SAs into laser cavities includes direct deposition of nanoparticles/thin-film-based SAs, tapered-fiber-based SAs, and D-shaped SAs. Furthermore, the paper explores the challenges encountered during the fabrication of ideal GO and rGO SAs, with issues related to uniformity, stability, and tunability, along with proposed solutions to address these challenges. The insights provided offer valuable guidance for future research aimed at enhancing the performance of EDFLs using GO/rGO SAs. Full article

Yellow-to-green electrochromic color switching plays a key role in the intelligent adaptive camouflage under the visible light environment in future military camouflage applications. Here, we designed and synthesized a soluble electrochromic conjugated pDPTD polymer, mainly based on perylo[1,12-bcd]thiophene and the novel ProDOT groups. The pDPTD polymer displayed a yellow-to-green electrochromism with large optical contrast and fast switching times. Based on the pDPTD polymer film, a yellow-to-green electrochromic device was achieved, showing an orange-yellow color at −0.4 V with L*a*b* color coordinates of 88.5, 18.5, and 34.2 and a pale green color at 0.7 V with L*a*b* color coordinates of 85.6, −4.8, and 11.5, together with a large optical contrast of 43.5% and fast switching times of 2.4/3.2 s. These results indicated that the pDPTD polymer could serve as a potential electrochromic material for yellow/green system camouflage applications. Full article

The pulse laser emission circuit plays a crucial role as the emission unit of time-of-flight (TOF) LiDAR. This paper proposes a nanosecond-level pulse laser diode array drive circuit for LiDAR, primarily aimed at addressing the issue of high-speed scanning drive for the laser diode array at the emission end of solid-state LiDAR. Based on the single pulse laser diode drive circuit, this paper innovatively designs a circuit that includes modules such as a boost circuit, linear power supply, high-speed gate driver, GaN field-effect transistor, and pulse narrowing circuit, realizing an 8-channel laser diode array drive circuit. This circuit can achieve a pulse laser array drive with a single channel operating frequency of greater than 100 kHz, an output pulse width of less than 5 ns, a peak power greater than 75 W, and a channel switching time that does not exceed 1 μs. A field programmable gate array (FPGA) is used to control the operation of this circuit and perform a series of performance tests. Experimental results show that this circuit has a high repetition rate, large output power, a narrow pulse width, and fast switching speeds, making it highly suitable for use in the optical emission module of solid-state LiDAR. Full article