Plasma Physics
A Propagator-based Multi-level Monte Carlo Method for Kinetic Neutral Species in Edge Plasmas
Gregory J. Parker, Maxim V. Umansky and Benjamin D. Dudson
We propose and investigate a new multi-level Monte Carlo scheme for numerical solutions of the kinetic Boltzmann equation for neutral species in edge
plasmas. In particular, this method explicitly exploits a key structural property of neutral particle dynamics: the prevalence of frequent collisions for which the outgoing velocity is determined by local
plasma parameters. Using this property, we derive a multi-level
algorithm based on collision event propagator and show, both analytically and through numerical experiments, that it reproduces the results of standard Monte Carlo methods. We further demonstrate that, in the context of coupled
plasma-neutral edge simulations employing correlated Monte Carlo, the proposed scheme retains trajectory correlation to machine precision as the system evolves, whereas conventional methods exhibit rapid decorrelation. These results indicate that the propagator-based multi-level Monte Carlo scheme is a promising candidate for use in fully implicit Jacobian-free Newton-Krylov (JFNK) solvers for coupled
plasma-neutral systems.
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Physics and Society
Functional Percolation: Criticality of Form and Function
Galen J. Wilkerson
Understanding how network structure constrains and enables information processing is a central problem in the statistical mechanics of interacting systems. Here we study random networks across the structural percolation transition and analyze how connectivity governs realizable input-output transformations under cascade dynamics. Using Erdos-Renyi networks as a minimal ensemble, we examine structural, functional, and information-theoretic observables as functions of mean degree. We find that the emergence of the
giant connected component coincides with a sharp transition in realizable information processing: complex input-output response functions become accessible, functional diversity increases rapidly, output
entropy rises, and directed information flow, quantified by transfer
entropy, extends beyond local neighborhoods. We term this coincidence of structural, functional, and informational transitions functional percolation, referring to a sharp expansion of the space of realizable input-output functions at the percolation threshold. Near criticality, networks exhibit a Pareto-optimal tradeoff between functional complexity and diversity, suggesting that percolation criticality may provide a general organizing principle of information processing capacity in systems with local interactions and propagating influences.
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Accelerator Physics
Real-Time-Capable Betatron Tune Measurement from Schottky Spectra Using Deep Learning and Uncertainty-Aware Kalman Filtering
Peihan Sun, Manzhou Zhang, Renxian Yuan et al. (+3 more)
Betatron tune measurement is essential for beam control in compact
proton-therapy synchrotrons, yet conventional peak-detection techniques are not robust under the low signal-to-noise ratio (SNR) conditions typical of these machines. This work presents a lightweight convolutional neural network that performs real-time tune extraction from Schottky spectra with sub-millisecond inference latency and calibrated uncertainty estimates. The model uses
attention-based pooling for reliable peak localization and a dual-branch architecture that jointly predicts the tune and its associated uncertainty. Trained with a Laplace negative log-likelihood loss, it produces uncertainty estimates whose magnitude tracks the instantaneous prediction error, which enables uncertainty-aware Kalman filtering for temporal smoothing. Experiments on a large synthetic
dataset spanning SNR levels from 0 to $-20$\,dB demonstrate substantial performance gains over traditional peak-detection baselines, while the Kalman filter further suppresses transient outliers in time-series operation. Preliminary validation on operational beam data confirms stable tune tracking without retraining. With only about $2.0\times 10^{4}$ trainable parameters and real-time inference on commodity GPU hardware, the proposed diagnostic offers a practical solution for rapid and accurate betatron tune monitoring in compact medical synchrotrons and similar accelerators.
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All authors Peihan Sun, Manzhou Zhang, Renxian Yuan, Deming Li, Jian Dong, Ying Shi
Applied Physics · Cross-listed from cond-mat.mtrl-sci
Single-crystalline high-quality beta-Ga2O3 pseudo-substrate on sapphire through sputtering for epitaxial deposition
Guangying Wang, Shuwen Xie, William Brand et al. (+10 more)
Solid-phase epitaxy (SPE) of beta-Ga2O3 thin films by
radio-frequency (RF) sputtering and then crystallized through high-temperature post-deposition annealing is employed on sapphire substrates, yielding a high-quality pseudo-substrate for subsequent buffer growth via MOCVD and LPCVD. Low roughness (<0.5 nm) and sharp single-crystalline diffraction peaks corresponding to the (-201), (-402), and (-603) reflections of beta-Ga2O3 were observed in the SPE beta-Ga2O3 film and the subsequent epitaxial buffer layer. N-doped Ga2O3 film on SPE Ga2O3 film grown by LPCVD showed step-assisted growth mode with reasonable electronic behavior with 45 cm^2/V-s mobility at a bulk carrier concentration of 1.3e17 cm^-3. These results suggest that SPE Ga2O3 is a promising pathway to advance the development of beta-Ga2O3 on foreign substrates.
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All authors Guangying Wang, Shuwen Xie, William Brand, Saleh Ahmed Khan, Ahmed Ibreljic, Darryl Shima, Yueying Ma, Brahmani Challa, Fikadu Alema, Andrei Osinsky, Anhar Bhuiyan, Ganesh Balakrishnan, Shubhra S. Pasayat
Applied Physics
Beta-Ga2O3 Sub-Micron FinFETs with Si Delta-Doped Channel Modulating Charge Density Above 3x10^13 cm^-2
Nabasindhu Das, Cameron Gorsak, Ankita Kashyap et al. (+6 more)
This letter reports on the design and demonstration of high-performance Beta-Ga2O3 FinFETs utilizing MOCVD-grown Si delta-doped channels to achieve enhanced carrier transport and electrostatic control. A record high sheet charge density of 3.3x10^13 cm^-2 was modulated using 100 nm fin channels, delivering a peak drain current of 410 mA/mm and a peak transconductance of 60 mS/mm. The FinFET architecture enables strong gate modulation, achieving a high Ion/Ioff ratio between 10^8 and 10^9. A low contact resistance of 0.42 ohm.mm was achieved to the Si delta-doped channel using MOCVD contact regrowth. Small-signal RF characterization revealed a current-gain cutoff frequency (fT) of 3.8 GHz and a maximum oscillation frequency (fMAX) of 2.1 GHz for a 0.8-micrometer gate length. These results demonstrate the efficacy of combining precision delta-doping with a 3D FinFET geometry for high-frequency Beta-Ga2O3 electronics, establishing a platform for future RF and high-power applications
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All authors Nabasindhu Das, Cameron Gorsak, Ankita Kashyap, Advait Gilankar, Pushpanshu Tripathi, Salil A Paranjape, Trevor Thornton, Hari Nair, Nidhin Kurian Kalarickal
Data Analysis and Statistics · Cross-listed from astro-ph.HE
The ONs and OFFs of Pulsar Radio Emission: Characterizing the Nulling Phenomenon
Garvit Grover, N. D. Ramesh Bhat, Samuel J. McSweeney et al. (+4 more)
Radio emission from
pulsars is known to exhibit a diverse range of emission phenomena, among which nulling, where the emission becomes temporarily undetectable, is an intriguing one. Observations suggest nulling is prevalent in many long-period
pulsars and must be understood to obtain a more comprehensive picture of
pulsar emission and its
evolution. One of the limitations in observational characterisation of nulling is the limited signal-to-noise, making individual pulses often not easily distinguishable from noise or any putative faint emission. Although some of the approaches in the published literature attempt to address this, they lose efficacy when individual pulses appear indistinguishable from the noise, and as a result, can lead to less accurate measurements. Here we develop a new method (the $\mathbb{N}$sum
algorithm) that uses sums of pulses for better distinguishability from noise and thus measures the nulling fraction more robustly. It can be employed for measuring nulling fractions in weaker
pulsars and observations with a limited number of observed pulses. We compare our
algorithm with the recently developed Gaussian Mixture Modelling approach, using both simulated and real data, and find that our approach yields consistent results for generic and weaker
pulsars. We also explore quasi-periodicity in nulling and measure the related parameters for five
pulsars, including PSRs~J1453$-$6413, J0950$+$0755 and J0026$-$1955, for which these are also the first such measurements. We compare and contrast our analysis of quasi-periodic nulling with previously published work and explore the use of
spin-down energy loss ($\dot E$) to distinguish between different types of modulation behaviour.
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All authors Garvit Grover, N. D. Ramesh Bhat, Samuel J. McSweeney, Christopher P. Lee, Chia Min Tan, Shih Ching Fu, Bradley W. Meyers
Plasma Physics
Generation of Polarization-Tunable Hybrid Cylindrical Vector gamma Rays
Si-Man Liu, Yue Cao, Kun Xue et al. (+11 more)
Cylindrical vector (CV) gamma rays can introduce spatially structured polarization as a new degree of freedom for fundamental research and practical applications. However, their generation and control remain largely unexplored. Here, we put forward a novel method to generate CV gamma rays with tunable hybrid polarization via a rotating electron beam interacting with a solid foil. In this process, the beam generates a coherent transition radiation field and subsequently emits gamma rays through nonlinear Compton scattering. By manipulating the initial azimuthal momentum of the beam, the polarization angle of gamma rays relative to the transverse momentum can be controlled, yielding tunable hybrid CV polarization states. Three-dimensional
spin-resolved particle-in-
cell simulations demonstrate continuous tuning of the polarization angle across (-90{\deg}, 90{\deg}) with a high polarization degree exceeding 60%. Our work contributes to the development of structured gamma rays, potentially opening new avenues in high-energy physics,
nuclear science, and laboratory astrophysics.
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All authors Si-Man Liu, Yue Cao, Kun Xue, Li-Xiang Hu, Xin-Yu Liu, Xin-Yan Li, Chao-Zhi Li, Xin-Rong Xu, Ke Liu, Wei-Quan Wang, De-Bin Zou, Yan Yin, Jian-Xing Li, Tong-Pu Yu
Optics
Scalable van der Waals Photonics: High-Refractive-Index Gallium Sulfide Films with Single-Crystal Optical Properties
Aleksandr Slavich, Georgy Ermolaev, Dmitriy Grudinin et al. (+15 more)
The integration of high-refractive-index dielectrics into scalable photonic architectures is foundational to advancing integrated
circuits and augmented reality (AR) displays. Van der Waals (vdW) materials offer exceptional optical properties, including high refractive indices and
giant anisotropy, but their implementation is constrained by the small area and uncontrolled thickness of mechanically exfoliated flakes. Here, we demonstrate that atomic layer deposition (ALD) grown gallium sulfide (GaS) overcomes the trade-off between high optical performance and manufacturability, emerging as a large-scale vdW dielectric platform. Through rigorous optical and structural benchmarking against pristine single
crystals, we establish that the optical constants (n, k) of ALD-GaS are virtually indistinguishable from single-
crystal counterparts. By leveraging the retained out-of-plane anisotropy, we demonstrate that ALD-GaS enables superior suppression of crosstalk in densely integrated waveguides compared to conventional scalable high-index platforms. Our findings establish ALD-GaS as a technologically viable pathway for implementing anisotropic vdW materials in visible-spectrum photonics.
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All authors Aleksandr Slavich, Georgy Ermolaev, Dmitriy Grudinin, Mikhail Tatmyshevskiy, Alexander Syuy, Nikolay Pak, Dmitry Yakubovsky, Mikhail Mironov, Adilet Toksumakov, Alexander Melentev, Elena Zhukova, Anton Minnekhanov, Gleb Tselikov, Ivan Kruglov, Sergey M. Novikov, Andrey Vyshnevyy, Aleksey Arsenin, Valentyn Volkov
Optics
Ionic Disorder-Mediated Exfoliation and Optical Birefringence in a Non-van der Waals Oxide
N. V. Pak, M. K. Tatmyshevskiy, I. A. Kruglov et al. (+11 more)
The landscape of two-dimensional photonics has been dominated by van der Waals (vdW) materials. Expanding this library to include non-vdW layered systems promises enhanced environmental robustness and access to novel functionalities, such as strong ionic conductivity, yet their exfoliation remains challenging. Here, we establish Na2Zn2TeO6 (NZTO), a P2-type superionic conductor, as an exfoliable non-vdW optical material. We demonstrate that the highly disordered, mobile Na+ interlayer inherently facilitates mechanical cleavage down to few-nanometer thicknesses (about 4 nm). Optical interrogation via spectroscopic ellipsometry reveals NZTO as a wide-bandgap dielectric with pronounced optical birefringence (Delta_n about 0.25) across the visible and near-infrared spectrum. The
lattice dynamics, probed by temperature-resolved Raman spectroscopy, underscore the
rigidity of the [Zn2TeO6]2- framework, which remains largely decoupled from the high ionic mobility. These results identify NZTO as a compelling platform for robust, anisotropic dielectric photonics, simultaneously opening a pathway toward the convergence of ionic transport and optical control - an emerging paradigm we term iono-photonics.
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All authors N. V. Pak, M. K. Tatmyshevskiy, I. A. Kruglov, K. V. Kravtsov, A. A. Minnekhanov, D. V. Grudinin, A. N. Toksumakov, A. S. Slavich, D. I. Yakubovsky, A. A. Vyshnevyy, M. A. El-Sayed, G. A. Ermolaev, A. V. Arsenin, V. S. Volkov
Computational Physics · Cross-listed from hep-ex
GEARS – A Fully Run-Time Configurable Geant4 Application
Jing Liu
The Geant4 toolkit is the standard for simulating the passage of particles through matter, but its conventional architecture often requires users to modify and recompile C++ code to alter fundamental simulation parameters such as geometry, physics list, and primary particle source. This architectural constraint introduces significant friction for new users and slows down the experimental iteration cycle. This paper introduces GEARS (Geant4 Example Application with Rich features yet Small footprint), a universally applicable Geant4 application that fundamentally addresses this issue. GEARS achieves complete simulation configurability without C++ recompilation by strictly utilizing external configuration methods: Geometry is defined via simple text-based configuration, the Physics List is selected via the standard PHYSLIST environment variable, and the Primary Source is defined through the General Particle Source (GPS) macro commands. Furthermore, regarding GEARS as an application instead of a framework, key features include a flat ntuple structure with short variable names for highly efficient analysis and a solution for capturing vital initial step data. Output creation is also fully managed via run-time macro commands and volume properties. The project is distributed as a ready-to-use Docker container to eliminate compilation barriers. Through these design considerations, GEARS transforms Geant4 into a practical, ready-to-use tool, enabling users to rapidly prototype and execute simulations for diverse experiments solely through simple text configuration files, without ever needing to modify or compile the underlying C++ source code.
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Plasma Physics
On How Zonal Fields Suppress Reversed Shear Alfvén Eigenmode in Tokamak Plasmas
Ruirui Ma, Pengfei Liu, Liu Chen et al. (+2 more)
Employing both nonlinear gyrokinetic simulations and theoretical analyses, we have discovered the novel result that, with energetic particle dynamics kept linear, the nonlinear suppression and eventual saturation of reversed-shear Alfvén eigenmode occur via the downward frequency chirping induced by the beat-driven zonal current. More specifically, as the mode frequency chirps downward, there is enhanced mode conversion to radially propagating electron Landau-damped kinetic Alfvén waves; resulting in enhanced convective (radiative) damping and, thereby, its suppression and saturation. Theoretical results are in good agreement with simulations both qualitatively and quantitatively.
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All authors Ruirui Ma, Pengfei Liu, Liu Chen, Fulvio Zonca, Zhiyong Qiu
Plasma Physics
Isotope Production in Fusion Systems
J. F. Parisi, J. A. Schwartz, S. E. Wurzel et al. (+2 more)
Fusion systems producing isotopes via
neutron-driven transmutation can achieve economic viability well before reaching energy breakeven. Incorporating carefully selected feedstock materials in a blanket allows fusion systems to generate both electrical power and high-value isotopes, expanding the space of viable concepts, significantly enhancing the economic value of fusion energy, and supporting an accelerated path to adoption. We calculate the value of this co-generation and derive a new economic breakeven condition based on net present value. At lower
plasma gain, $Q_{\mathrm{plas}}\lesssim 1$, high-value transmutation, such as medical radioisotopes, enables pure transmuter fusion systems operating at only watts to megawatts of fusion power: for example, a 3 megawatt system transmuting ${}^{102}\mathrm{Ru}\rightarrow{}^{99}\mathrm{Mo}$ could fulfill global ${}^{99}\mathrm{Mo}$ demand with $Q_{\mathrm{plas}} \ll 1$. At higher gain $Q_{\mathrm{plas}}\gtrsim 3$, it becomes viable to generate electricity in addition to isotopes. For example, co-production of electricity and gold, transmuted from mercury in a fusion blanket, can reduce the required
plasma gain for economic viability from $Q_{\mathrm{plas}}\sim 10$-$100$ to $Q_{\mathrm{plas}}\sim 3$-$5$. We further highlight techniques to enhance transmutation with asymmetric
neutron wall loading. Fusion
neutron-driven transmutation therefore offers a revenue-positive pathway for deploying fusion energy at terawatt-scale, starting from smaller watt-to-megawatt-scale machines for radioisotope production and then scaling up to co-producing electricity and gold in larger fusion power plants.
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All authors J. F. Parisi, J. A. Schwartz, S. E. Wurzel, A. Rutkowski, J. Harter
Applied Physics · Cross-listed from cond-mat.mtrl-sci
Predicting tunable nonreciprocal spin wave generation mediated by interfacial Dzyaloshinskii-Moriya interaction in magnonic heterostructures
Cameron A McEleney, Karen L Livesey, Robert E Camley et al. (+1 more)
Thin, metallic
magnetic films can support nonreciprocal
spin waves due to the interfacial Dzyaloshinskii-Moriya interaction (iDMI). However, these films typically have high damping, making
spin wave propagation distances short (less than one micrometer). In this work, we theoretically study a thin
ferromagnetic strip with iDMI and excite
spin waves by driving a central segment of the strip.
Spin waves propagate with different amplitudes to the left versus to the right from the driving region (i.e. nonreciprocity occurs) due to the iDMI. Our calculation based on
spin-wave-dispersion plus our micromagnetic simulations both show that changing the driving segment width, driving frequency and static applied field strength tunes the nonreciprocity. Our calculation based on
spin-wave-dispersion, using a so-called "overlap function" will allow researchers to predict conditions of maximum nonreciprocity, without the need for computational solvers. Moreover, to circumvent the issue of short propagation distances, we propose a geometry where iDMI is only present in the driving region and low-damping materials comprise the remainder of the strip. Our calculations show significant
spin wave amplitudes over several microns from the excitation region.
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All authors Cameron A McEleney, Karen L Livesey, Robert E Camley, Rair Macêdo
Instrumentation and Detectors
Non-invasive Techniques for Flow Rate Measurement in Water Pipes: Protocol for a Systematic Review
Juan Diego Belesaca and Fabian Astudillo Salinas
Accurate, non-invasive flow measurement is imperative for efficient water resource management and leak detection in distribution systems. Despite the advent of diverse external sensing technologies, a paucity of consolidated evidence exists regarding their comparative performance, energy efficiency, and applicability in varied operational contexts. The document delineates the protocol for a systematic literature review (SLR) that aims to identify, evaluate, and synthesize the extant evidence on non-invasive flow monitoring techniques for piped networks. Adhering to the Kitchenham methodology, the review will investigate the accuracy, precision, and energy consumption of prevailing solutions, such as ultrasonic and accelerometer-based systems. The analysis will also assess the impact of signal processing and machine learning (ML)
algorithms on enhancing system capabilities. The objective of this study is to map the state-of-the-art, identify key research gaps, and provide an empirical foundation to direct future research toward operational deployment.
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Plasma Physics · Cross-listed from astro-ph.SR
Tracing a Multi-Temperature Quiescent Prominence's Thermodynamic Evolution from Sun to Earth
Callie A. García, Yeimy J. Rivera, Samuel T. Badman et al. (+5 more)
Solar prominences are cool, dense stable structures routinely observed in the corona. Prominences are often ejected from the Sun via coronal mass ejections (CMEs). However, they are rarely detected in a cool, low-ionized state within CMEs measured in situ, making their
evolution hard to study. We examine the thermodynamic
evolution of one of these rare cases where a quiescent prominence eruption clearly preserves its low-ionized charge state as evidenced by in situ detection. We use multi-viewpoint Extreme Ultraviolet (EUV) observations to track and estimate the density, temperature and speed of the prominence as it erupts. We observe that part of the prominence remains in absorption well beyond initial liftoff, indicating the bulk of the prominence experiences minimal ionization and suggesting any strong heating is balanced by radiative losses, expansion, or conduction. From its subsequent in situ passage near 1au, charge states reveal that the prominence is composed of both cool, low-ionized ions as well as hotter
plasma reflected by the presence of highly ionized iron, Fe$^{16+}$. Simulated non-
equilibrium ionization and recombination results using observationally derived initial conditions match the in situ multi-thermal state for a prominence composed of 70% cool
plasma with a 1.8MK peak temperature, and 30% hot
plasma with a 4.3MK peak temperature. This suggests that the prominence may not be heated uniformly or that parts of it cools more rapidly. The complex, multi-thermal nature of this erupting prominence emphasizes the need for more comprehensive spectral observations of the global corona.
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All authors Callie A. García, Yeimy J. Rivera, Samuel T. Badman, John C. Raymond, Katharine K. Reeves, Tatiana Niembro, Kristoff W. Paulson, Michael L. Stevens
Biological Physics · Cross-listed from quant-ph
Parallel accelerated electron paramagnetic resonance spectroscopy using diamond sensors
Zhehua Huang, Zhengze Zhao, Fei Kong et al. (+7 more)
The nitrogen-vacancy (NV) center can serve as a
magnetic sensor for electron paramagnetic resonance (EPR) measurements. Benefiting from its atomic size, the diamond chip can integrate a tremendous amount of NV centers to improve the
magnetic-field sensitivity. However, EPR spectroscopy using NV ensembles is less efficient due to inhomogeneities in both sensors and targets. Spectral line broadening induced by ensemble averaging is even detrimental to spectroscopy. Here we show a kind of cross-relaxation EPR spectroscopy at zero field, where the sensor is tuned by an amplitude-modulated control field to match the target. The modulation makes detection robust to the sensor's inhomogeneity, while zero-field EPR is naturally robust to the target's inhomogeneity. We demonstrate an efficient EPR measurement on an ensemble of roughly 30000 NV centers. Our method shows the ability to not only acquire unambiguous EPR spectra of free radicals, but also monitor their spectroscopic dynamics in real time.
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All authors Zhehua Huang, Zhengze Zhao, Fei Kong, Zhecheng Wang, Pengju Zhao, Xiangtian Gong, Xiangyu Ye, Ya Wang, Fazhan Shi, Jiangfeng Du
Physics and Society
Evaluating the Impact of Population Growth and Applying Decarbonization Regulations on the Energy Market in the ERCOT Interconnection Area
Farah Altarazi
Texas ERCOT is experiencing rapid population growth that increases electricity demand and creates new reliability challenges. At the same time, decarbonization policies are being considered, adding uncertainty about future generation portfolios and system costs. This study evaluates how population driven load growth and proposed decarbonization regulations may affect ERCOT in 2030 using a capacity expansion model. Three population scenarios are analyzed: baseline, lower growth, and higher growth. For each scenario, additional cases introduce a CO2 emissions limit and a carbon price to assess their effects on system costs, generation mix, and non served energy. Results show that population growth increases total system costs and unmet demand, while storage needs and transmission transfer levels remain relatively stable. A CO2 emissions limit has almost no effect because ERCOT is already expected to meet the 2030 threshold. In contrast, carbon pricing produces a meaningful shift toward renewable generation and reduced use of natural gas, although cost impacts vary by scenario. These findings show the importance of accounting for demographic uncertainty in long term planning and suggest that carbon pricing may be a more effective decarbonization mechanism than static emissions limits. The study also provides a basis for future
stochastic modeling that incorporates uncertainty in demand, renewable output, and fuel prices.
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Applied Physics · Cross-listed from cond-mat.mes-hall
Skyrmion Sliding Switch in a 90-nm-Wide Nanostructured Chiral Magnet
Yaodong Wu, Jialiang Jiang, Weiwei Wang et al. (+5 more)
Magnetic skyrmions, renowned for their fascinating electromagnetic properties, hold potential for next-generation topological spintronic devices. Recent advancements have unveiled a rich tapestry of 3D topological magnetism. Nevertheless, the practical application of 3D topological magnetism in the development of topological spintronic devices remains a challenge. Here, we showcase the experimental utilization of 3D topological magnetism through the exploitation of skyrmion-edge attractive interactions in 90-nm-wide confined
chiral FeGe and CoZnMn
magnetic nanostructures. These attractive interactions result in two degenerate
equilibrium positions, which can be naturally interpreted as binary bits for a skyrmion sliding switch. Our theory and simulation reveal current-driven spiral motions of skyrmions, governed by the anisotropic gradient of the potential landscape. Our experiments validate the theory that predicts a tunable threshold current density via
magnetic field and temperature modulation of the energy barrier. Our results offer an approach for implementing universal on-off switch functions in 3D topological spintronic devices.
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All authors Yaodong Wu, Jialiang Jiang, Weiwei Wang, Lingyao Kong, Shouguo Wang, Mingliang Tian, Haifeng Du, Jin Tang
Plasma Physics
Activation of Polylactic Acid and Polycarbonate Surfaces with Non-Thermal Plasma
Jairo Rondón, Ginger Urrutia and Angel Gonzalez-Lizardo
Non-thermal
plasma (NTP) surface activation has become a powerful and versatile strategy to engineer the interfacial properties of biomedical
polymers whose intrinsic hydrophobicity limits their biological performance. In
polymers such as polylactic acid (PLA) and polycarbonate (PC), NTP promotes the controlled incorporation of polar functional groups, increases surface energy, modifies dielectric behavior, and generates micro-roughness that collectively enhance
protein adsorption and early
cell adhesion. This review synthesizes and critically evaluates evidence across four complementary analytical pillars-contact-angle theory, dielectric impedance spectroscopy, FT-IR chemical mapping, and optical microscopy-to construct an integrated framework for interpreting
plasma-induced chemical and morphological transformations. The convergence of
multimodal results demonstrates that NTP consistently produces chemically active, polar, and moderately textured surfaces that support robust initial
cell-material interactions. Furthermore, combining wettability, dielectric, and spectroscopic analysis enables the identification of activation pathways, the assessment of hydrophobic recovery dynamics, and the development of quantitative correlations between dielectric parameters and biological response. However, the literature also reveals key methodological gaps, including the limited use of unified
multimodal protocols, insufficient evaluation of temporal stability, and a lack of predictive dielectric-biological models. By articulating these advances and limitations within a unified conceptual scheme, this review provides a roadmap for future research aimed at standardizing characterization workflows and enabling the rational design of next-generation
plasma-functionalized biomaterials for tissue-engineering scaffolds, implantable devices, and advanced drug-delivery systems.
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