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Electromagnetically induced transparency-like effects in silicon metasurfaces have attracted considerable interest due to their capability to manipulate optical resonances and improve sensing performance. In this work, a U-shaped silicon metasurface is proposed, consisting of a horizontal nanopillar supporting bright mode and two vertical nanopillars supporting dark mode. The coupling and coherent interference between the bright and dark modes lead to a pronounced EIT-like effect at specific wavelengths. By introducing nanoscale gaps between the horizontal and vertical silicon pillars, a U-shaped silicon metasurface with gap mode (UG metasurface) is formed, which induces strong near-field enhancement and is associated with reduced radiative losses, thereby improving the quality factor of the EIT-like resonance of UG metasurfaces. Two silicon metasurface samples are fabricated, and their transmission spectra are experimentally measured, showing good agreement with numerical simulations. In addition, the refractive index sensing performance of silicon metasurfaces is numerically investigated. The results show that the UG metasurface design significantly enhances the sensing capability, increasing the figure of merit from 6 RIU-1 to 60 RIU-1. The proposed silicon metasurfaces and near-field enhancement with the gap-mode mechanism provide a promising strategy for realizing high-performance optical sensing and offer valuable insights into the manipulation of electromagnetic responses.

To investigate the multi-factor aging mechanisms of silicone rubber used in the outer sheath of composite bushings, this study focused on HTV silicone rubber employed in the sheath layer of 1100 kV high-voltage bushings. The samples were subjected to temperature-humidity-corona coupled aging in a multi-factor aging platform. The aged samples were characterized by scanning electron microscopy, energy-dispersive spectroscopy, Fourier-transform infrared spectroscopy, hydrophobicity measurements, hardness tests, and dielectric constant measurements. The results indicate that different aging factors affect the material differently. Corona aging primarily affects the sample surface, leading to substantial methyl group detachment, surface oxidation, and a decrease in hydrophobicity, with the local static contact angle decreasing by up to 70%. In contrast, wet heat aging affects the bulk material; under high-temperature and high-humidity conditions, the internal small-molecule chains accelerate silicon-oxide crosslinking, leading to a marked increase in hardness and a relative dielectric constant that initially decreases and then increases. Considering the complex field environment, surface performance measurements are easily influenced by external factors. Therefore, hardness and relative dielectric constant are proposed as key indicators for evaluating the aging degree of silicone rubber sheaths in service. The findings provide a valuable reference for the service-life evaluation of composite bushings.

Microelectromechanical systems are being increasingly deployed in nuclear industry robotics, where their great sensitivity and mechanically stable silicon structures enable reliable sensing in radiation-exposed environments. An ultra-thin silicon strain gauge without an oxide substrate layer designed for robotic electronic skin is evaluated under Co-60 γ irradiation, representative of nuclear decommissioning conditions. The sensor performance is evaluated based on electrical measurements conducted before and after irradiation, focusing on cumulative radiation-induced effects. The results show that silicon strain gauge signal maintains a high linearity (R2 > 0.99) under strain. Across an accumulated dose range up to approximately 15 Gy, only minor variations are observed, including a resistance increase within 1.3% and a reduction in gauge factor within 5% for most specimens. The radiation-induced resistance increases and sensitivity degradation results in a maximum strain estimation error of approximately 22.5 με (≈3.5%) within the tested operating range below 700 με.

The fabrication of semiconductor devices using submicron- and nanometer-scale silicon structures is based on lithography (patterning on a substrate) and etching (transferring a pattern onto the substrate) technologies. These processes typically require complex and expensive equipment, as well as extensive experimental optimization of etching parameters, especially for structures with an aspect ratio greater than 10. This work demonstrates a productive and relatively simple approach for fabricating an ordered array of vertically oriented monolithic silicon tubes with high-aspect-ratio internal cavities. The creation of these structures is based on Langmuir-Blodgett colloidal lithography, vacuum magnetron sputtering, and a continuous plasma etching process performed at "room" temperature of the substrate holder. To develop the fabrication process for high-aspect-ratio (>10) structures, we employed Bayesian optimization (a machine learning method), which proved highly efficient in reducing the number of experiments compared to a full factorial analysis. The resulting silicon tubes exhibited an average total reflectance of 3.7% over the 200-1600 nm wavelength range.

Liquid silicone rubber (LSR) materials are often used in the manufacture of flexible circuit board substrates for wearable devices. However, traditional processing techniques limit the improvement of the molding precision and make it difficult to process complex structures. Three-dimensional (3D) printing is a novel manufacturing method for LSR wearable devices. The influence of the internal temperature field on LSR's curing time was evaluated. The printing performance and mechanical properties were analyzed with three inks (SiO2/PEG/LSR, PEG/LSR, and LSR) with polyethylene glycol (PEG) and silicon dioxide (SiO2) modifying LSR. Furthermore, orthogonal experiments were conducted to optimize the material ratios, and the entropy weight method was applied to establish a comprehensive evaluation function that incorporates printable duration, tensile strength, and needle blockage. Under the optimal printing temperature (25 °C), it was clear that the performance of SiO2/PEG/LSR was the best. The forming accuracy of its line width was 98.5%, the tensile strength was 72.96% higher than pure LSR, and the impact strength remained at ∼6.1 MPa (equivalent to pure LSR). Orthogonal analysis confirmed the LSR dosage as the most significant influence on printability and mechanical properties, and the optimized material ratio was determined as LSR:PEG:SiO2 = 300:30:1 (by weight). The optimized materials combined with rheological experiments have demonstrated that integrating the thermal history with material modification to improve the printing performance of extrusion-based 3D printing is effective.

Nitric oxide (NO) is a gaseous biocompatible radical molecule with demonstrated biomedical and antimicrobial benefits. Developing adaptable, long-lasting delivery systems for NO has become an essential goal for both combating resistant bacterial growth and providing sustained medical benefits. Silsesquioxane (SQ)-based organogels were chosen and synthesized as robust, tunable NO-release platforms. These highly stable SQ gel frameworks, composed of silicon-oxygen backbones with variable R groups, exhibited high porosity and surface area and offered chemical versatility, enabling control over NO loading and release. 3-Mercaptopropyl groups were utilized as sulfur-based NO-releasing substituents (-RSNOs), with additional R groups capable of altering accessibility to RSNO sites through hydrophobicity and steric hindrance. The NO release profile, rate, and duration of the functionalized gels were also tailored by adjusting the number of RSNO sites in the elastomeric system, thereby enabling a customizable release profile. This combination of NO-releasing silsesquioxanes with silicone elastomers yields composite materials that are integratable into biomedical applications, offering NO release up to 40 days within modeled physiological conditions in PBS buffer.

Nanohybrid semiconductors comprising distinct nanoscale components offer new opportunities for tailored optoelectronic properties. In this work, Zn3N2-CN x hybrid thin films were prepared by reactive RF magnetron sputtering from a segmented Zn/graphite target and used to fabricate p-Si heterojunction photodetectors. The hybrid-film approach was explored as a route to modify the electronic character of a Zn3N2-rich sputtered overlayer and its junction response on silicon. X-ray diffraction and microscopy indicated a heterogeneous nanostructured film, Raman spectroscopy showed retention of a CN x -like disordered carbon-nitride network, and elemental mapping confirmed spatial coexistence of Zn, N, and C with a measurable O contribution in the as-deposited layer. Optical analysis revealed characteristic energies associated with the Zn3N2-rich and CN x -containing components. The Zn3N2-CN x /p-Si heterojunction exhibited an ideality factor of ∼2.9, a rectification ratio of ∼13.7 at 5 V, a maximum responsivity of ∼0.40 A W-1 at 550 nm, and a detectivity of ∼2.03 × 1011 Jones, together with stable transient switching and rise/recovery times of ∼0.5/0.7 ms. The results support the formation of an electronically distinct hybrid overlayer whose incorporation is associated with improved heterojunction photodetection on p-Si. Reactively sputtered Zn3N2-CN x therefore represents a promising hybrid thin-film platform for Si-based optoelectronic devices.

Chemical extrasynaptic signaling in the mammalian brain is involved in the control of behavior via modulation of neural activity, in wiring the brain by directing the axonal growth, in localization of pharmacological effects of drugs, and in regulating the neuroinflammation. Local gradients of various neurochemicals in the brain are difficult to study in vivo due to their complex spatiotemporal dynamics induced by intricate interactions between neurons and glial cells that are not well understood. Here, to directly measure in vivo gradients of multiple neurotransmitters and metabolites simultaneously, we utilize an open-flow silicon nanodialysis sampling platform coupled with sensitive mass spectrometry. Results reveal strong millimeter-scale spatial gradients in concentration of neurotransmitters, neuromodulators, and astroglial modulators in a mouse cortex. Formation and maintenance of such local chemical compartments indicate strong regulation of brain neurochemistry by glial-neuron interactions that may heavily influence physiological and pathophysiological modulation of brain functions.

As the paradigm of modern medicine shifts toward prevention and management, the importance of implantable electronics for real-time physiological monitoring and therapeutic intervention has surged, yet the mechanical mismatch between conventional rigid devices and soft tissues poses significant challenges regarding inflammation and long-term performance. Consequently, this review hierarchically analyzes advanced semiconductor integration strategies for flexible and stretchable implantable systems, utilizing Silicon Nanomembrane (SiNM) technology as a core building block to achieve mechanical compliance while maintaining CMOS compatibility. We systematically examine flexible substrate processing and patterning techniques, including laser-induced graphene (LIG) and printing methods, and place special emphasis on conformal encapsulation strategies using inorganic/organic multilayer thin films to ensure miniaturization and reliability in harsh biological environments. Furthermore, the review covers system-level integration issues, including hierarchical wireless communication strategies tailored to implantation depth and hybrid energy harvesting technologies for battery-free operation, ultimately proposing that the organic integration of these elements is essential for realizing next-generation "Fully Autonomous Bio-integrated Systems".

Ruthenium silicide (Ru-Si) is a technologically important 4d transition metal silicide, and theoretical calculations suggest the possibility of a new Si-rich phase. The novel ruthenium silicide, RuSi3, was successfully synthesized under high-pressure and high-temperature (HPHT) conditions of 4-14 GPa and 800-1000 °C. This compound was not theoretically predicted and was discovered experimentally for the first time in this study, making it the most Si-rich ruthenium silicide reported to date. It crystallizes in a monoclinic C2/c structure with a = 13.48423(14) Å, b = 7.54146(4) Å, c = 7.98416(8) Å, and β = 123.5351(6)°. DFT calculations indicate that RuSi3 becomes enthalpically stable above 1 GPa compared to the starting phase, which is consistent with the experimental results. The dependence of the synthesis conditions and HPHT in situ XRD experiments suggest that increasing the pressure enhances the reactivity and lowers the temperature required for synthesis. RuSi3 has a semimetallic and pseudogap electronic structure and contains a short Si-Si covalent bond network connecting the Ru-Si polyhedra. Our findings not only suggest the possibility of discovering novel silicon-rich transition metal silicides but also unequivocally demonstrate that high-pressure synthesis is an effective strategy for significantly expanding the structural diversity of this compound class.

Soil salinity severely constrains strawberry production by disrupting ion homeostasis and provoking oxidative injury. This study investigated whether soluble silicon (Si) and activated carbon (AC) act to enhance salt tolerance in strawberry (Fragaria × ananassa). Under NaCl stress, plants showed pronounced growth inhibition, increased Na+ accumulation and a deteriorated K+/Na+ balance, accompanied by elevated reactive oxygen species (ROS) and lipid peroxidation. In contrast, combined AC + Si treatment consistently provided the strongest protection, improving seedling vigor and survival. Relative to NaCl alone, AC + Si increased shoot and root fresh weight by 67.5% and 78.5%, reduced shoot Na+ by 59.1%, and lowered shoot H2O2 and MDA by 62.6% and 66.5%, respectively, indicating marked improvement in ion-redox homeostasis. Beyond plant responses, AC-containing treatments alleviated salt-induced increases in soil electrical conductivity, coinciding with a clear restructuring of the rhizosphere bacterial community and enrichment of putatively beneficial taxa. Transcriptome profiling further supported coordinated reprogramming of ion transport, redox control and stress-responsive signaling pathways under the AC + Si regime. Collectively, the results indicated that Si and AC co-application enhances strawberry salt tolerance through an integrated soil-plant-microbiome mechanism that stabilizes ion homeostasis and reinforces redox homeostasis.

The construction of a high-quality interface with excellent surface passivation and carrier transport is critical to the device performance of solar cells. Low-dimensional perovskite structures are widely explored for surface passivation due to their effective suppression of interfacial defects and enhanced environmental stability. While terminal molecules for constructing low-dimensional structures provide excellent passivation, they can introduce potential barriers for charge transport if the energy levels are not well-aligned. Herein, a tryptamine molecule is explored as the terminal molecule for the construction of a low-dimensional structure for passivating the buried interface of perovskite solar cells. Based on the inclusion of nitrogen atoms in the aromatic heterocyclic structure, the terminal molecule shows an uplifted HOMO level that aligns well with the perovskite skeleton, giving rise to enhanced orbit coupling. Therefore, this low-dimensional structure enables excellent surface passivation and interfacial carrier transport simultaneously, generating an outstanding open-circuit voltage (VOC) up to 1.266 V and an efficiency of 23.53% for single-junction wide-bandgap (1.68 eV) perovskite solar cells. This improvement enables the fabrication of the perovskite/silicon tandem solar cell with an efficiency of 33.22% (32.88% assessed by a third party) and a VOC of 1.987 V. Moreover, the fast carrier transport at the interface suppressed the halide phase segregation, bringing much enhanced operation stability.

In the rapidly evolving field of single-molecule sensing, solid-state nanopores have emerged as transformative tools for the label-free detection of biomolecules, ranging from DNA polymers to proteins. Yet, with two dominant platforms─glass nanopores and silicon nitride (SiNx) nanopores─researchers face a pivotal choice: which architecture best unlocks superior performance? Here, we deliver a head-to-head experimental comparison under comparable experimental conditions, benchmarking noise characteristics, signal-to-noise ratios (SNRs), and translocation dynamics for DNA and protein analytes across matched nanopore sizes. Our findings reveal compelling trade-offs: glass nanopores excel in DNA sensing, achieving record SNR values of >80 in 5 nm nanopores (4 M LiCl, 50 kHz filter cutoff) due to their conical geometry that focuses electric fields. In contrast, SiNx nanopores dominate protein detection with SNR values of >120, leveraging thin membranes for enhanced current blockade from volume exclusion. Comprehensive performance metrics─including unfolded DNA fraction, backward-to-forward translocation time ratio, translocation frequency, and perturbed events─also show distinct translocation behaviors of biomolecules in the two nanopore platforms. These insights, supported by finite-element simulations, establish a mechanistic framework for nanopore selection, favoring conical glass nanopores for polymeric analytes and SiNx membrane nanopores for compact biomolecules. This work not only sets benchmarks for nanopore sensitivity but also enables the development of tailored sensors in diagnostics, sequencing, and beyond, advancing nanotechnology for high-resolution biomolecular analyses.

A multi-mode interferometer (MMI) spectrometer is a type of reconstructive micro-spectrometer based on imaging light propagation patterns in MMI waveguides. A waveguide scattering surface accentuates imaging light patterns in the multi-mode interferometer. This technology has been proven with an SU-8 core waveguide with an etched SU-8 nanograss scattering surface. This paper describes our creation of a fully silicon-based spectrometer using a silica core MMI waveguide. Scattering features were created in silica using SU-8 nanograss as an etch mask in a reactive ion etch (RIE). With optimized etch parameters, the silica core MMI spectrometer achieved an SNR of three with an incident light power of -68 dBm, which was almost 6 dB lower than designs with an SU-8 core.

Circularly polarized luminescence (CPL) from quantum dots (QDs) is interesting for quantum optics, spintronics, and chiral photonics. We report CPL from Si QDs covalently functionalized via vinyl or acetylene linkers with structurally chiral binaphthyl-based ligands, investigating the interplay between binding geometry, surface structure, and chiroptical response. Circular dichroism (CD) spectroscopy reveals that monodentate ligands do not induce chiral transitions associated with the QD, indicating ineffective chirality transfer. In contrast, bidentate vinyl-bridged ligands induce clear, mirror-image CD and circularly polarized luminescence (CPL) signals associated with electronic transitions from the QD, confirming successful chirality transfer. ATR-IR spectroscopy shows that these chiral binaphthyl ligands transition from bidentate to monodentate binding with increasing surface coverage, correlating with a nonmonotonic trend in electronic absorption and bandedge emission dissymmetry factors, gabs and glum with maxima at 2.34 × 10-3 and 8.87 × 10-4 respectively which peak at ∼3 ligands per QD. High-resolution transmission electron microscopy reveals that ligand binding induces lattice compression in the QDs, likely associated with chirality. These findings highlight the crucial role of ligand binding geometry and surface-induced structural distortion in generating chiroptical activity in Si QDs for next-generation chiral nanomaterials.

Background: Photodynamic therapy (PDT) offers a promising complementary strategy for treating glioblastoma multiforme (GBM); however, limited control over photosensitizer activation and reduced efficacy under hypoxic conditions remain significant limitations. Methods: In this study, we present the synthesis and functional evaluation of Gal-SiX, an enzymatically activatable Si-xanthene-based activatable PDT agent designed to address these challenges. Prepared via an improved 10-step synthetic route, Gal-SiX exhibits clear turn-on fluorescence and absorbance responses upon β-galactosidase activation and efficiently generates reactive oxygen species in aqueous media. Results: Mechanistic studies revealed that Gal-SiX enables both Type I and Type II PDT pathways, a favorable feature for GBM environments characterized by restricted oxygen availability. In vitro assays conducted on U87MG glioblastoma cells and L929 healthy fibroblasts demonstrated light-dependent cytotoxicity, with IC50 values of 3.30 μM and 7.19 μM, respectively. Gal-SiX also showed minimal dark toxicity (>80 μM) and potent light-induced cytotoxicity, yielding a phototoxicity index of 24.8 in glioblastoma cells. Confocal imaging and MTT assays consistently confirmed enzymatic activation and effective PDT response at the cellular level. Conclusions: Overall, this work introduces the first activatable Si-xanthene-based PDT agent for glioblastoma and provides the first evidence that the Si-xanthene scaffold can support dual Type I/II phototoxicity. These results underscore Gal-SiX's potential as a PDT platform for addressing the unique constraints of GBM biology.

Hafnium-oxide-based ferroelectric field-effect transistors are widely regarded as strong candidates for embedded nonvolatile memory, but their practical deployment remains limited by premature endurance failure, typically after only about 104 program/erase cycles. Here, we show that this loss of device functionality is not caused by intrinsic degradation of the ferroelectric layer. By examining the same electrically degraded gate stack after memory-window closure, we find that robust polarization switching is still preserved, demonstrating that the ferroelectric medium remains functional, even when transistor-level memory operation has collapsed. The origin of failure instead lies at the interface, where charge trapping and the associated electrostatic screening progressively reduce the threshold-voltage contrast between the programmed states. As a result, the device loses its ability to operate as a memory transistor even though the underlying ferroelectric stack continues to switch. These findings provide direct evidence that endurance in hafnium-oxide-based ferroelectric transistors is governed primarily by interface degradation rather than by true ferroelectric fatigue.

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Donor-based quantum devices in silicon are attractive platforms for universal quantum computing and analog quantum simulations. The nearly atomic precision in dopant placement promises great control over the quantum properties of these devices. We present atomistic calculations and a detailed analysis of many-electron states in a single phosphorus atom and selected phosphorus dimers in silicon. Our self-consistent method involves atomistic calculations of the electron energies utilizing representative tight-binding Hamiltonians, computations of Coulomb and exchange integrals without any reference to an atomic orbital set, and solutions to the associated Hartree-Fock equations. First, we assess the quality of our tight-binding Hartree-Fock protocol against configuration-interaction calculations for two electrons in a single phosphorus atom, finding that our formalism provides an accurate estimation of the electron-electron repulsion energy requiring smaller computational boxes and self-consistent single-electron wavefunctions. Then, we compute charging and binding energies in phosphorus dimers observing their variation as a function of impurity-impurity separation. Our calculations predict an antiferromagnetic ground state for the two-electron system and a weakly bound three-electron state in the range of separations considered. We rationalize these results in terms of the single-electron energies, charging energies, and the wavefunction reshaping.