Search Results (502)

We propose a novel self-coupled optical waveguide (SCOW+) architecture that enhances spectral control in integrated photonic circuits. Derived from the foundational SCOW platform, SCOW+ introduces a tunable ring resonator coupled with an all-pass filter to achieve sharp, periodic transmission dips with adjustable free spectral range and extinction ratio. This hybrid configuration supports multifunctional behavior, enabling the device to operate as a narrowband filter, modulator, or sensor depending on the tuning parameters. The SCOW+ structure leverages self-coupling and phase interference to induce coupled-resonator-induced transparency, offering fine control over spectral features. Using frequency-domain simulations, we validate the spectral response and tunability of SCOW+. Simulation results confirm that the device exhibits flexible tuning capabilities and dynamic reconfiguration of its transmission profile by adjusting ring length and coupling coefficient. SCOW+ enhances spectral shaping without significantly increasing device size. Its modularity and compatibility with standard fabrication processes underscore its potential for scalable integration in silicon photonics platforms. The results of this study highlight the versatility of SCOW-derived architectures and enable compact, tunable photonic components in next-generation integrated systems. Full article

Background/Objectives: Commercially available drug-eluting stents still suffer from poor blood compatibility, polymer coating delamination, polymer cracking and lack of stability during and after stent implantation that led to adverse events such as stent thrombosis and in-stent restenosis. This article highlights the advantages of using silicon nanofilament (SiNf) as an interface between stent surface and drug-in-polymer coating or bloodstream. Methods: Thin layer of SiNf was successfully formed on the surface of Co-Cr substrate via one-step simple method. For stent applications, sirolimus-in-poly(D,L-lactide) (PDLLA/SRL) matrix was coated on control and SiNf-modified Co-Cr substrates and the stability, cracking, and long-term degradation was compared. Blood compatibility studies were also compared between control and SiNf-modified Co-Cr substrates. Results: The morphology of the filaments showed nanosized structures with nano-gaps between the filaments which support mechanical interlocking of PDLLA/SRL coating and enhanced the coating stability with no coating delamination whereas, the control substrate presented 97% of coating delamination. The PDLLA/SRL coating on stent platform demonstrates smooth and uniform morphology without webbing between stent struts. After stent ballooning, the control stent presented cracking and peeling of the polymer coating from the surface whereas, the SiNf-modified stent did not show any signs of these unfavorable defects. Moreover, SiNf-modified surface showed reduced fibrinogen adsorption and lower number of platelet adhesion with round shape morphology. Conclusions: Overall, this suggests that modifying the metallic substrates with SiNf could act as a universal coating for reinforcing the polymer coating stability, prevent coating defects that accompany stent ballooning, and improve the blood compatibility of the material surfaces that could have various applications to medical implants and devices. Full article

Red- and near-infrared (NIR)-emissive quantum dots (QDs) hold great promise in optoelectronic devices, sensors, and biomedicine owing to their advantages of low optical scattering, deep-tissue penetration, and compatibility with advanced photonic technologies. However, the toxicity of conventional cadmium (Cd)- and lead (Pb)-based QDs has led to growing demand for eco-friendly alternatives. Here, we provide a comprehensive review of sustainable classes of red/NIR-emissive QDs, including indium phosphide (InP), I-III-VI chalcogenides (CuInS₂, AgInSe, and so on), group-IV (Si, Ge, and SiGe) nanocrystals, and carbon-based QDs (graphene QDs or carbon dots). InP QDs are leading candidates for display technologies due to their high efficiencies and narrow bandwidths in emission properties, enabled by advanced core/shell engineering. In contrast, I-III-VI chalcogenides, group-IV, and carbon-based QDs offer advantages for biocompatible NIR bioimaging, photothermal therapy, and silicon photonics integration. We discuss synthesis strategies for achieving long-wavelength emission, the mechanisms of red/NIR photoluminescence (PL), and representative applications in displays, sensors, and bioimaging. Finally, we outline the remaining challenges, such as large-scale manufacturing and long-term stability, which should be addressed for commercial and clinical viability. Full article

SiSn alloys have attracted growing interest for group-IV bandgap engineering, although their epitaxial growth remains challenging due to the extremely low equilibrium solubility of Sn in Si. In this work, fully strained (pseudomorphic) SiSn epitaxial layers were grown on Si (001) substrates by means of molecular beam epitaxy. A systematic investigation reveals a strong inverse correlation between growth temperature and Sn incorporation efficiency. Despite a constant Sn flux, the incorporated Sn composition decreases from 5.5% to 3.2% as the growth temperature increases, indicating a pronounced temperature dependence of Sn incorporation. Reflection high-energy electron diffraction indicates a gradual transition of the growth from two-dimensional to three-dimensional with increasing film thickness. Structural characterization by means of X-ray diffraction, atomic force microscopy, and transmission electron microscopy confirms the pseudomorphic growth and smooth surface morphology and reveals twins and stacking faults near the surface region. These results establish a quantitative reference for SiSn growth kinetics and provide guidance for future studies of SiSn and SiGeSn alloys in silicon-compatible electronic and optoelectronic applications. Full article

Braided nerve guidance conduits (NGCs) composed of decellularized porcine small intestinal submucosa (SIS) were developed to achieve an appropriate balance between mechanical performance and biological compatibility for peripheral nerve repair. This study aimed to compare four SIS-braided conduits with silicone tubes in terms of bending compliance, tensile strength, swelling behavior, and cytocompatibility. SIS-braided conduit exhibited a favorable combination of flexibility, tensile strength, and dimensional stability. In vitro evaluations using PC12 and SW10 cells demonstrated that SIS-braided conduit supported neurite outgrowth and Schwann cell adhesion, confirming its favorable cytocompatibility. Based on these findings, SIS-braided conduits and silicone tubes were subsequently evaluated in a rat sciatic nerve defect model. Functional recovery assessed using the Sciatic Functional Index suggested preliminary functional recovery in the SIS-braided conduit, and histological analyses revealed evidence of axonal regeneration and myelin formation within the conduit. Overall, the results indicate that the integration of mechanical robustness with biological activity is essential for the design of nerve graft substitutes. The conduit braided from decellularized small intestinal submucosa represents a promising biodegradable alternative, a considerable biodegradable alternative to conventional non-degradable silicone conduits for peripheral nerve repair. Full article

The on-chip detection of circularly polarized light is pivotal for advancing applications in quantum optics, information processing, and spectroscopic sensing. However, conventional chiral metasurfaces often suffer from complex multilayer fabrication, material incompatibility, or modest performance, hindering their integration with photonic circuits. Here, we introduce a monolithic all-silicon metasurface that overcomes these limitations through a singular structural innovation. By strategically truncating four corners of a conventional Z-shaped meta-atom, we induce a hybridization of optical modes that profoundly enhances chiral light–matter interaction. This deliberately engineered perturbation yields a colossal circular dichroism with an extinction ratio exceeding 66 dB, a performance that surpasses existing state-of-the-art designs by approximately three orders of magnitude. Furthermore, the proposed metasurface exhibits remarkable fabrication robustness, owing to its single-layer architecture and CMOS-compatible material. We demonstrate that this exceptional metasurface can be directly integrated with a Mercury Cadmium Telluride (MCT) photodetector to form a highly efficient, compact circular polarization detector. Our work provides a simple yet powerful paradigm for creating high-performance chiral photonic devices, paving the way for their widespread adoption in integrated optoelectronics. Full article

The present theoretical study proposes and unravels chemical graft modification using a novel voltage stabilizer (3-amino-5-chlorophenyl 3-fluorophenyl methanone, ACFM) to ameliorate electrical insulation performance, oxygen-resistant characteristics, and thermal stability of addition-cure silicone rubber (SiR) used for cable accessory insulation in power transmission systems. First-principles calculations demonstrate that chemically grafted ACFM introduces shallow hole and electron traps into addition-cure SiR macromolecules to respectively impede hole transport and restrict hot electron production. Through molecular dynamics and Monte Carlo simulation, the chemically grafted ACFM is verified to enhance chain segment coalescence and decrease oxygen compatibility of addition-cure SiR macromolecules due to its higher dipole moment, leading to a reduction in oxygen permeation and improvement in thermal stability of the SiR crosslinked material. It is indicated from first-principles oxidation reaction paths that chemical grafting ACFM contributes positively to the oxidative stability of addition-cure SiR. The improved abilities of charge trapping and withstanding high temperatures together with enhanced resistance to both oxygen infiltration and oxidation of the addition-cure SiR material, as unraveled on a molecular scale in this research, open an avenue for developing advanced polymer dielectrics applied in harsh environments. Full article

Epoxy resin (E-51) exhibits excellent adhesion and is widely used in the preparation of functional composite coatings. However, its smooth surface lacking micro/nano composite structures limits its self-cleaning capability and optical properties. Direct incorporation of organic silicone or inorganic fillers often faces severe phase separation and filler agglomeration issues, resulting in defects in coating durability and weather resistance. To address these challenges, this study developed a synergistic modification strategy integrating surface energy modulation with the architectural design of micro/nano-structures. Amino-terminated PDMS undergoes ring-opening addition reactions with epoxy groups in the epoxy resin, while functionalized barium sulfate nanoparticles modified with dual silane coupling agents are incorporated to enhance optical properties. This synergistic approach not only resolved interfacial compatibility but also endowed the PDMS@EP-BaSO₄ coating with outstanding comprehensive properties; the water contact angle increased to 123.5°, demonstrating an easy-to-clean benefit. Visible light reflectance reached 95%, and emissivity rose to 90%. Furthermore, when applied to metal surfaces, the coating exhibited excellent stability against acid–alkali–salt corrosion, extreme temperatures, and ultrasonic agitation. This work provided a novel approach for developing protective coatings that integrated high reflectance, high emissivity, and long-term anti-soiling properties. Full article

The growing demand for intelligent environmental monitoring is driving the advancement of high-performance, low-cost, and highly integrated gas sensors. Silicon-compatible semiconductor gas sensors provide a promising platform to achieve this goal by leveraging their compatibility with complementary metal–oxide semiconductor (CMOS) processes. The established mass-manufacturing capabilities of micro-electromechanical systems (MEMS) and the high sensitivity and signal amplification characteristics of field effect transistors (FETs) in recent years have made the development of next-generation sensing devices feasible. In this review, we systematically summarize the latest advances in silicon-compatible gas sensors, with a focus on MEMS and FET technologies. We discuss their sensing mechanisms and performance optimization strategies, and further highlight the evolution of gas sensor technology toward on-chip intelligent olfactory systems that integrate sensing, computing, and storage capabilities. Full article

Prefilled syringes are valuable drug delivery systems, offering convenience and precision dosing. Among the critical factors influencing their performance is the stability of the silicone oil layer, which acts as a lubricant, guaranteeing the gliding properties of the plunger. The silicone oil, if it comes in contact with therapeutic formulations, can be subject to drug–container interactions, potentially leading to silicone oil release into the solution, thereby altering the gliding properties of the syringe and leading to unwanted particle formation, compromising drug efficacy and safety. Different measurement techniques, such as visual inspection, dynamic light scattering and spectroscopic analysis, are used to assess silicone oil layer stability in prefilled syringes. However, a quantitative, rapid and low-volume screening method to rapidly evaluate container compatibility for therapeutic formulations is not available. Here, we present a multi-well-based screening protocol allowing users to quantify, through fluorescence, the silicone oil released into a solution upon contact with liquid formulations. Fluorescently labeled uniform silicone oil layers of the desired thickness are deposited in glass-bottom wells and exposed to typical formulations, containing surfactants and monoclonal antibodies. The release of silicon oil as a function of contact time is quantified using fluorescence calibration. Beyond its use as a screening tool to evaluate drug–container compatibility, our protocol can contribute to the fundamental understanding of the factors and mechanisms influencing silicone oil layer stability and, furthermore, to the optimization of drug delivery systems. Full article

Polymer–ceramic hybrid composites are emerging as attractive candidates for lightweight, corrosion-resistant absorber components in solar thermal collectors; however, their adoption is constrained by the intrinsically low thermal conductivity of polymers, processing-induced anisotropic heat transport, interfacial thermal resistance at tube/laminate joints, and durability challenges under outdoor exposure. This review provides a collector-centered synthesis of polymer–ceramic hybrid materials, emphasizing the translation of composite properties into collector-level outcomes rather than conductivity enhancement alone. A structure–property–performance mapping approach is presented to connect directional thermal conductivity ((k_in-plane), (k_perp)), thermal diffusivity, heat capacity, coefficient of thermal expansion, and service temperature with collector performance parameters such as heat removal effectiveness, overall heat losses, and stagnation behavior. Ceramic fillers (e.g., boron nitride, aluminum nitride, silicon carbide, alumina) are examined for stable conduction-network formation, coating compatibility, and long-term reliability, while carbon fillers (graphite, graphene nanoplatelets, carbon nanotubes) are evaluated for combined heat spreading and solar absorption benefits, with attention to emissivity penalties. Hybrid ceramic–carbon architectures and multilayer absorber designs are identified as the most promising routes to balance thermal transport, optical selectivity (high solar absorptance and low thermal emittance), manufacturability, and durability under UV, humidity, and thermal cycling. Full article

The growing demand for sustainable, biocompatible, and multifunctional sensing materials has intensified interest in melanin and its derivatives, including melanin-inspired polymers and composites. Melanin is a naturally occurring biopolymer whose intricate structure and diverse chemical composition give rise to a remarkable combination of optical, electrical, and chemical properties. Key physicochemical characteristics, such as broadband optical absorption, hydration-dependent conductivity, redox activity, and metal ion coordination, are closely linked to melanin’s signal transduction capabilities and underpin its relevance in sensing applications. Recent advances in melanin-based sensing technologies encompass pH, humidity, chemical, biological, and optical platforms, with particular emphasis on hybrid systems incorporating graphene, silicon, or nanomaterials, and printable or wearable device architectures. These developments have enabled enhanced performance and broadened potential application fields. However, persistent challenges, including intrinsic heterogeneity, limited selectivity, relatively low electrical conductivity, and poor long-term operational stability, still limit practical implementation. Emerging molecular engineering and advanced fabrication strategies are being developed to address these limitations. Together, these findings position melanin as a versatile, eco-compatible, and functionally rich material, with a significant potential to underpin the next generation of sustainable sensing technologies. Full article

As surface-active functional compounds, defoamers play a pivotal role in seawater desalination processes. In this study, a polyether-modified silicone compound was synthesized, and its structure was confirmed through FITR and ¹H-NMR characterization. Using this compound as the main component, a more effective and stable composite defoamer product was obtained through a co-optimization method. The particle size of the defoamer ranged from 600 to 700 nm in aqueous systems, and the surface tension could be reduced to 27.46 mN/m, thereby exhibiting superior defoaming and antifoaming properties. Additionally, the defoamer demonstrated good compatibility with commonly used scale inhibitors and was non-corrosive to equipment. Industrial testing further confirmed its efficacy in controlling foam during seawater desalination effectively. Full article

The continuous scaling of microelectronic technology nodes has imposed fundamental physical constraints on conventional floating-gate (FG) non-volatile memory, driving the adoption of charge-trapping memory such as Silicon–Oxide–Nitride–Oxide–Silicon (SONOS) technology. SONOS devices offer advantages in scalability, endurance, and compatibility with advanced CMOS processes, yet their high-temperature reliability remains challenging due to charge loss mechanisms influenced by device structure and material properties. In this work, we systematically evaluate the reliability of two-transistor SONOS memory fabricated using a 28 nm high-K metal gate (HKMG) process. A refined temperature-dependent charge loss model (T-model) is introduced, which, by incorporating a characteristic temperature parameter (T₀) that captures the dynamic shift in activation energy, fundamentally departs from the constant-activation energy assumption of the conventional Arrhenius model. This approach more accurately describes charge retention behavior across a wide temperature range. Experimental results demonstrate excellent device performance, including endurance exceeding 10⁴ program/erase cycles at 85 °C and data retention over 10 years at 85 °C. The T-model shows strong agreement with measured data, providing a physically grounded framework for predicting long-term reliability. This study not only validated a novel charge loss model, providing insights for predicting the failure time of SONOS memory, but also demonstrated that HKMG-integrated SONOS memory exhibits high reliability. Full article

Electromagnetic compatibility (EMC) diagnostics for high-density through-silicon via (TSV)-based chips face significant challenges due to complex three-dimensional electromagnetic coupling and inefficient source reconstruction workflows. This paper proposes a universal contribution-driven dipole preprocessing technique tailored for dipole array-based source reconstruction methods, addressing the critical efficiency-accuracy trade-off inherent in traditional approaches. The core innovation is an influence factor-based evaluation-elimination mechanism that extracts effective dipole components aligned with the structural characteristics of TSV-based chips and multilayer printed circuit boards, while eliminating redundant dipoles independently of the downstream source reconstruction algorithm. Validation on a multilayer PCB (1 GHz) and a TSV-based chip (4 GHz) demonstrates that the technique maintains high reconstruction accuracy, with error increase limited to ≤0.2% for the simulated PCB and ≤0.05% for the physically measured TSV-based chip. Computational time is reduced by 28–61% for the PCB and 20–28% for the TSV chip compared to traditional source reconstruction without preprocessing. For TSV-based chips exhibiting complex electromagnetic behavior, the technique delivers consistent performance across different dipole configurations, providing a fast, robust, and universal EMC diagnostic tool for high-density electronic devices. Full article