Browse Articles

A novel KRT17-hnRNP K-CXCR3 axis promotes esophageal squamous cell carcinoma metastasis via nuclear-cytoplasmic redistribution

Oxidation degradation of TiN electrodes in DRAM capacitors and mitigation through AlN insertion

Given the increasing demand for high-performance capacitors in dynamic random access memories (DRAMs), boosting the dielectric constant (k) to maximize capacitance density becomes critical, which requires the mitigation of low-k interfacial oxidation layers between the TiN electrodes and the dielectrics. This study investigated the effect and mechanism of TiN oxidation under controlled annealing conditions, which resulted in a significant decrease in the dielectric constant due to dielectric relaxation and degraded reliability. To address this issue, we introduced an AlN insertion layer as an oxygen diffusion blocking layer, which effectively prevented interfacial oxidation. The AlN layer not only preserved the dielectric constant of the capacitors, it also reduced leakage current and enhanced device reliability. These findings systematically summarized the consequences of TiN interfacial oxidation, a common phenomenon observed in DRAM fabrication, and demonstrated the potential of AlN layers in enhancing the performance of TiN-based capacitors in advanced electronic applications.

Influenza A virus derived NS1 enhances translation of HPLC purified mRNA and interferon adjuvanted mRNA vaccination

214 MW/cm2 vertical <i>β</i> -Ga2O3 UMOSFETs enabled by HF sidewall treatment

Vertical β-Ga2O3 U-shaped trench structures (UMOSFETs) incorporating current-blocking layers typically suffer from increased on-resistance, primarily caused by deep-level defect states in the trench sidewalls that trap free electrons. In this study, the hydrofluoric acid (HF) sidewall treatment was introduced prior to gate dielectric deposition to modify the trench surface. This process enables the effective incorporation of fluorine atoms into the sidewall region, increasing the electron concentration and mitigating the compensation associated with deep acceptor levels from heavy nitrogen implantation. As a result, the forward conduction is improved. In addition, the HF treatment partially passivates surface and interface traps and provides a mild polishing effect, which slightly reduces surface roughness. These changes help suppress interface scattering and further enhance carrier transport. The fabricated vertical β-Ga2O3 UMOSFETs achieved a specific on-resistance of 6.0 mΩ cm2, a channel mobility of 19.1 cm2/V s, and a breakdown voltage of 1132 V. These results demonstrate that HF sidewall treatment provides a simple and efficient surface engineering approach for significantly enhancing the conduction performance and overall electrical characteristics of β-Ga2O3 UMOSFETs.

Modeling of the Arabian/Nubian shield’s geothermal structure: a multi-parametric analysis using geophysical and geological tools

Abstract The Arabian-Nubian Shield (ANS) is a complex Neoproterozoic tectonic mosaic whose lithospheric structure and geothermal regime remain poorly constrained. Here, for the first time across the entire ANS, we integrate S-wave tomography, seismic velocity models, lithospheric density from Gravity Field and Steady-State Ocean Circulation Explorer (GOCE) satellite data, and Land Surface Temperature (LST) derived from Moderate Resolution Imaging Spectroradiometer (MODIS) imagery to map crustal and upper mantle architecture. Results show stark lithospheric contrasts: the stable Arabian Platform has thick, cold lithosphere (Moho depth ~ 32.5 km, lithosphere-asthenosphere boundary (LAB) &gt; 200 km) and low heat flow (40–50 mW/m²), whereas the Arabian Shield and Red Sea rift exhibit thin lithosphere (Moho 25–30 km, LAB 60–120 km) with high heat flow (70–90 mW/m²). These areas display low S-wave velocities (≤ 3920 m/s), reduced mantle density, and high-temperature anomalies indicative of active mantle upwelling and lithospheric thinning. This multi-parametric framework identifies zones of pronounced lithospheric thinning as prime targets for geothermal exploration across the ANS and provides new insight into its Cenozoic geodynamic evolution.

Modulation of Fe doping tail for high CW power handling and OIP3 in HEMT-based RF switches compatible with PA co-integration

In this work, we present the first investigation into the impact mechanism of Fe doping tails on the radio frequency (RF) switching performance of AlGaN/gallium nitride (GaN) high electron mobility transistors (HEMTs). It is illustrated that a thicker unintentionally doped (UID) GaN layer combined with a thinner Fe-doped buffer layer significantly reduces Fe concentration in the near-channel region of the UID GaN layer. HEMTs with weaker Fe doping tails exhibit superior RF switching performance. This phenomenon occurs as the Fe tailing effect during high-power RF switch operation aggravates the dynamic resistance degradation of the series HEMT and modifies the channel potential distribution, which in turn induces a large vertical component capacitance in the shunt HEMT. Fabricated switch devices with 500 nm gate length on the optimized epitaxial structure demonstrated outstanding performance: Pmax = 32 dBm at 3.6 GHz under −10 V gate bias, and Pmax &amp;gt; 38 dBm with OIP3 = 56 dBm at −20 V gate bias. These experimental results demonstrate that controlled Fe tail effect engineering enables HEMTs to achieve both high-power handling and high linearity simultaneously, demonstrating a viable approach for developing high-performance RF switches compatible with Fe-doped buffer power amplifiers.

Denoising eye movement signals using a novel signal processing framework to preserve oculomotor integrity in dyslexia

The mechanism of single-event burnout in NiO/ <i>β</i> -Ga2O3 heterojunction diodes under atmospheric neutron irradiation

This study investigates the mechanism of single-event burnout (SEB) in NiO/β-Ga2O3 heterojunction diode (HJD) induced by atmospheric neutron. The degradation mode and physical mechanism are evaluated through current–voltage (I–V) measurement, emission microscopy, technology computer-aided design (TCAD), focused ion beam (FIB), and scanning electron microscopy (SEM) analysis. The experimental results indicate that the reverse bias voltage is a critical factor influencing SEB failure of NiO/β-Ga2O3 HJD. SEB occurs when the reverse bias reaches 750 V, characterized by a sharp increase in cathode current and catastrophic failure. Electrical characterization after SEB shows complete loss of rectifying behavior and reverse voltage withstand capability. TCAD simulations indicate that secondary particles generated by neutron interactions produce electron–hole pairs along their trajectory, which accelerate under the strong electric field in the drift layer, triggering impact ionization and current surge. Intense impact ionization leads to lattice temperature exceeding the melting point of β-Ga2O3, causing thermal runaway and burnout. FIB and SEM analysis confirms melt voids spanning the entire drift layer and part of the substrate, consistent with simulation results. These findings clarify the SEB mode and mechanism in NiO/β-Ga2O3 HJD and provide insights for evaluating their performance in harsh radiation environments.

A real-time mobile aquatic plant recognition algorithm based on deep learning for intelligent ecological monitoring

Spectroscopic investigation of Fermi level pinning at metal oxide/polymer interfaces and implications for built-in voltage

The built-in potential (Vbi) critically governs charge injection and transport in organic and hybrid optoelectronic devices. While self-assembled monolayers (SAMs) are commonly used to tune electrode work functions, whether this tuning directly translates into controllable Vbi remains unresolved due to possible Fermi level pinning. This study systematically investigates how interface pinning influences the energy level landscape and Vbi in poly[N,N′-bis(4-butylphenyl)-N,N′-bis(phenyl)benzidine] (poly-TPD) diodes fabricated on SAM-modified NiOx substrates. By tailoring the substrate work function (Φsub) with SAMs, we achieve precise tuning over a wide range (4.3–5.7 eV). Combining electro-modulated absorption spectroscopy, Kelvin probe measurements, and numerical simulations, we find that pinning emerges in poly-TPD when Φsub ≥ 4.7 eV and quantify how Vbi evolves in both pinned and unpinned regimes. The simulations reproduce the observed transition, which is triggered when Φsub exceeds a threshold of approximately 4.9 eV, corresponding to the hole-accepting level in poly-TPD with a state density of ∼2 × 1020 cm−3. Furthermore, both the interfacial potential bending in the pinned state and the polaron signal intensity increase monotonically with Φsub. This work reveals that charge transfer between the substrate and polymer pins Vbi, an insight that provides a mechanistic basis for interface designing in oxide/SAM-based organic electronic devices.

Optimizing virtual power plant coordination through locational marginal flexibility under network constraints

Strain-engineered photogalvanic anisotropy in SnP2X6 (X = S, Se) monolayers for high-performance optoelectronics

The photogalvanic effect (PGE) in non-centrosymmetric materials can generate stable currents without external bias, holding significant potential for optoelectronic applications. However, the limited absorption range and weak photoresponse in conventional materials have hindered practical applications. Herein, we investigate the strain-engineered PGE in SnP2X6 (X = S, Se) monolayers, a class of chalcogenophosphate materials featuring strong visible-to-near-infrared absorption and intrinsic anisotropy. First-principles calculations reveal that both uniaxial and biaxial strain significantly modulate the electronic structure and lattice asymmetry, leading to a remarkable enhancement in PGE. Notably, the photocurrent exhibits remarkable anisotropy, with the armchair direction response being ∼40 times and ∼4 times stronger than that along the zigzag direction in SnP2Se6 and SnP2S6 monolayers, respectively. Additionally, a 2% tensile strain along the armchair direction enhances the photocurrent by one order of magnitude compared to the unstrained state. These findings not only reveal the underlying mechanism of strain-tuned PGE but also establish SnP2X6 as a versatile platform for designing polarization-sensitive, broadband, and high-efficiency optoelectronic devices.

Deep learning-based classification of thyroid nodules using uncertainty-aware multi-modal ultrasound imaging

Chiral-sensitive frequency mixing in valley-excited two-dimensional semiconductors

Two-dimensional (2D) semiconductors endowed with valley degree of freedom offer potential applications in next-generation petahertz valleytronics and photonics for emerging quantum technologies. We experimentally and theoretically uncover striking signatures of nonperturbative nonlinear optical response in valley-selective photodoped monolayer molybdenum disulfide, highlighting the interplay between strong-field dynamics and valley polarization. The interplay of valley-assisted excitation and circularly polarized probe leads to chiral-sensitive sum and difference frequency mixing of the pump and probe photons, appearing as sidebands in the high-harmonic spectra. Interestingly, the sideband's strength depends on the photodoped valley's chirality and the weaker pump's helicity. Additionally, a circular dichroic signal results from valley-selective photodoping when the pumps's helicity is changed. Sensitivity of the sideband's strength on the pump–probe delay bears an imprint of the temporal aspect of the electron–hole coherence in 2D semiconductors.

Generation of a large-diameter diffuse plume in an atmospheric pressure argon plasma jet with a single tube

From a practical application viewpoint, the generation of a large-diameter plume is of great importance for the atmospheric pressure plasma jet. In this Letter, a large-diameter argon plume is generated downstream of a single-tube plasma jet with a simple needle-plate geometry. Results indicate that the diffuse plume is composed of a semi-spherical discharge close to the needle tip, a trumpet-like discharge on the top of the plate, and a dark region between them. Photoelectric measurement reveals that there is a broad hump with a duration time of &amp;gt;100 μs in the light signal per negative voltage half cycle. By fast photography, spatiotemporal evolution of the diffuse plume is investigated, which indicates that the semi-spherical discharge corresponds to a corona near the needle tip, and the trumpet-like discharge operates in a Townsend discharge regime. Optical emission spectroscopy is used to characterize electron excitation temperature and electron density, both of which decrease in the semi-spherical corona discharge and increase in the trumpet-like Townsend discharge with increasing distance from the needle tip.

Nonlinear symmetry breaking to enhance the Sagnac effect in a microresonator gyroscope

Optical gyroscopes based on the Sagnac effect have been widely used for inertial navigation in aircraft, submarines, satellites, and unmanned robotics. With the rapid progress in the field of ultrahigh-quality whispering gallery mode and ring resonators in recent years, these devices offer the promise of a compact alternative to ring laser gyroscopes and fiber optic gyroscopes. Yet, the successful commercialization of a microresonator gyroscope has been hindered by the scaling of the Sagnac effect with resonator area. While several techniques have been proposed to enhance the Sagnac effect in microresonators, these enhancements also amplify the thermal noise in the microresonator. Here, we present an approach to measuring the Sagnac signal in chip-scale devices that overcomes this fundamental noise limitation to achieve unprecedented performance in a 200 μm optical resonator—the smallest reported to date. Our proof-of-concept design shows a 104 enhancement of the Sagnac signal while simultaneously suppressing thermal noise by 27 dB and environmental contributions to noise by 22 dB. We believe this approach offers a pathway to compact integrated photonic gyroscopes that reach the sensitivity required for inertial navigation.

Surface-localized magnetic order in RuO2 thin films revealed by low-energy muon probes

Ruthenium dioxide (RuO2) has recently emerged as an altermagnetic candidate, but its intrinsic magnetic ground state in thin films remains widely debated. This study aims to clarify the nature and spatial extent of the magnetic order in RuO2 thin films grown under different conditions. Thin films of RuO2 with thicknesses of 30 and 33 nm are deposited by pulsed laser deposition and sputtering onto TiO2(110) and Al2O3(1¯102) substrates, respectively. Low-energy muon spin rotation/relaxation (LE-μSR) with depth-resolved sensitivity measurements is performed in transverse magnetic fields (TF) from 4 K to 290 K. The μSR data collected with a muon implantation energy of 1 keV reveal that magnetic signals originate from the near-surface region of the film (≲10 nm), and the affected volume fraction is approximately 8.5%. The localized magnetic response is consistent across different substrates, growth techniques, and parameter sets, suggesting a common origin related to surface defects and dimensionality effects. The combined use of TF-μSR and the study of depth-dependent implantation with low-energy muons provides direct evidence for surface-confined, inhomogeneous static magnetic order in RuO2 thin films, helping reconcile discrepancies. These findings underscore the importance of considering reduced-dimensional contributions and motivate further investigation into the role of defects, strain, and stoichiometry on the magnetic properties of RuO2, especially at the surface.

Quantitative resolution of grain boundary impedance in Ce-doped Li7La3Zr2O12 through the distribution of relaxation time analysis and electrochemical performance in quasi solid-state batteries

Li7La3Zr2O12 (LLZO) garnets have many characteristics that make these materials a good solid electrolyte for Li-ion batteries, but their poor interfacial properties and limited ionic conductivity continue to limit their widespread applications. In this study, Ce-doped LLZO has been comprehensively analyzed through x-ray diffraction (XRD), scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS), tunneling electron microscopy-energy dispersive spectroscopy (TEM-EDS), impedance spectroscopy with distribution of relaxation times, and testing of cell experimentally. XRD confirmed the dominant cubic phase with minor Ce-rich secondary phase, while SEM/TEM-EDS shows dense grains with flaky structure along with the homogeneous distribution of elements. Electrochemical testing of symmetric cell indicates lower polarization voltage and stability up to 700 h, while quasi solid-state battery with LiFePO4 as cathode leads to capacity retention of 72% after 24 cycles.

Achieving high carrier concentration β-Ga2O3 epilayers via MOCVD using SiCl4 as dopant

Gallium oxide (Ga2O3) transparent conductive electrodes and power-device contact layers are critical components for Ga2O3-based electronics. However, the intrinsically low electron mobility (μ) of the (100) plane, which is preferred for large-scale substrate production, under high carrier concentration (n) has hindered device performance and practical deployment. To overcome this bottleneck, we employed unintentionally miscut (100) substrates and optimized thermal and kinetic conditions to achieve step-flow homoepitaxy with ideal surface morphology. Following the elimination of surface Si contamination, in situ Si doping was performed utilizing silicon tetrachloride (SiCl4). SiCl4 proved highly effective for fabricating high-n homoepilayers, yielding films with high crystalline quality, low surface roughness, and more than 80% optical transmittance in the 260–800 nm range. Notably, at a SiCl4 doping flux of 10.4 nmol/min, the homoepilayer exhibited outstanding electrical properties (n = 1.32 × 1019 cm−3, μ = 55.5 cm2 V−1 s−1). These findings not only outperform previously reported results for (100) homoepilayers grown on intentionally miscut substrates but also rival the performance of state-of-the-art (010) plane epilayers.

High-current, high-voltage AlN p–n junction diodes enabled by compositional grading

AlN p–n junction diodes with low specific ON-resistance (1.6 mΩ cm2), enabling forward current densities &amp;gt;1 kA/cm2, and reverse breakdown fields of 8 MV/cm, were demonstrated. The quasi-vertical device structure consisted of a p-AlGaN anode, an n-AlN drift layer, and an n-AlGaN back contact. The effect of the AlGaN/AlN band offset was studied by comparing devices with abrupt and compositionally graded junctions. Simulation and experimental data suggested that the valence band offset at the abrupt junction significantly limited hole injection into the AlN, limiting the forward current. This problem was mitigated with the use of a compositionally graded junction that showed an order of magnitude higher ON-state current density. These results show that high-current, high-breakdown AlN p–n junction diodes can be achieved by using compositional grading to circumvent the doping problem in p-type AlN.