bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparison of spoke dynamics in an obstructed direct-current magnetron operating on a range of noble gases
Authors: Przybocki R C , Cappelli M A 
Published: January 2025

Abstract
Fluctuations in discharge current are observed using a segmented anode on a direct-current planar magnetron discharge. The oscillations have frequencies in the 350–3400 kHz range and are indicative of coherent plasma structures propagating in the closed-drift azimuthal direction, commonly referred to as ‘rotating spokes.’ The structures are studied across a range of discharge and ambient pressure conditions for the inert gases neon, argon, krypton, and xenon. It is found that the argon, krypton, and xenon plasmas exhibit a transition from spoke propagation opposite the

E

×

B

drift direction at low current densities to propagation in

E

×

B

at higher current densities. This reversal occurs at a threshold current density of 5–17 mA

cm

−
2

, depending on the pressure and ion species. The wave dispersion properties of the oscillations are also studied, and the transition to

+

E

×

B

-directed modes is shown to be accompanied by lower frequencies and higher phase velocities. The number of spoke structures exhibits a non-linear dependence on pressure and current. The frequency and wavenumber of the disturbances are modeled with a similarity solution that suggests a dependence on the critical ionization velocity in the wave dispersion, which points to ionization wave phenomena governing the spoke dynamics.
Collisional radiative model based investigation on the color appearance of xenon plasma in Hall thruster plumes
Authors: Feng Kun , Zhang Zhongkai , Qi Jiayun , Yi Tianlang , Zhang Guangchuan , Wang Yibai , Zhang Zun , Ren Junxue , Wang Weizong , Tang Haibin 
Published: January 2025

Abstract
Hall thruster is a type of electric propulsion system used for spacecraft. The study of the Hall thruster plume, which is a plasma, reveals the thruster’s performance. Images of Hall thruster operating can be found from various online sources, the thruster plumes are typically transparent with a slight blue or green hue. However, some plumes are colorful instead of being monochromatic, with distinguishable regions. In this study, we investigated the xenon plasma color using a collisional radiative model and explained the color appearance of Hall thruster plumes. We show that xenon atoms and ions appear in different colors. For a standard observer, singly charged xenon ions appear in green, irrespective of the plasma environment. Xenon atoms, on the other hand, can appear blue, violet, or magenta. Through the investigation, we found that the resulting plasma color is related to the mass utilization efficiency and ion velocity of the thruster plume. We introduce an approach to produce color from collisional radiative models, where we use color as a property of the plasma, and demonstrate its usefulness for plasma studies.
Electron dynamics and particle transport in capacitively coupled Ar/O2 discharges driven by sawtooth up voltage waveforms
Authors: Dong Wan , Gao Zhuo-Yao , Wang Li , Zhang Ming-Jian , Tian Chong-Biao , Liu Yong-Xin , Song Yuan-Hong , Schulze Julian 
Published: January 2025

Abstract
One dimensional fluid/electron Monte Carlo simulations of capacitively coupled Ar/O2 discharges driven by sawtooth up voltage waveforms are performed as a function of the number of consecutive harmonics driving frequencies of 13.56 MHz, N (1–3), pressure (200–500 mTorr) and gas mixture (10%–90% admixture of O2 to Ar). The effects of these external parameters on the electron dynamics, and the transport of ions and neutrals are revealed at constant peak-to-peak driving voltage. The electronegativity is found to decline as the number of consecutive harmonics increases and the DC self-bias voltage decreases. Increasing the pressure also leads to a decrease in electronegativity. The combination of a decrease in the mean free path of electrons and the presence of the electrical asymmetry effect result in different spatio-temporal distributions of the ionization rate, which lead to a reduction in the amplitude of the DC self-bias at higher pressure. As the admixture of electronegative O2 increases, the electronegativity is enhanced, and the discharge mode changes from an α—drift ambipolar (DA) hybrid to DA mode. This work focuses on linking these fundamental changes of the plasma physics induced by changing external parameters to process relevant charged particle and neutral fluxes to the electrodes. Particular attention is paid to O(1D) flux, because it is a precursor of deposition. In discharges driven by sawtooth up voltage waveforms, placing the substrate on the grounded electrode and increasing the number of consecutive harmonics, N, can facilitate the deposition process, since the O(1D) flux to the substrate is higher in these scenarios. Moreover, at an O2 admixture of 20%, the O(1D) flux is nearly as high as that at an O2 admixture of 90%, indicating that a higher O(1D) flux can be achieved without excessively increasing the O2 admixture.
Research on hybrid processing of silicon carbide based on laser cutting
Authors: Wang Jinhu , Jiang Kai , Yue Xiuhui , Zhang Qianyong , Wang Cuishan , Jing Xueting , Wang Jing , Tang Wenjing , Xia Wei 
Published: January 2025

Abstract
With the rapid development of semiconductor technology, silicon carbide has been widely used in various power electronic device. However, the material has an extremely high hardness ranking second only to diamond, which makes processing difficult. In this work, the two methods of laser cutting and dicing saw are utilized to test the cutting process of silicon carbide respectively, then the appropriate through-cutting process parameters are obtained. The two methods are combined to compare the cutting quality of the three approaches. As a result, the laser cutting is affected by heat with through-cutting 0.5 mm-thick silicon carbide, which results in the rough front-surface edge and much residue, and the cutting groove of the back surface is irregular. The dicing saw having more mechanical stress, resulting in serious tool wear, prone to chipping and micro-cracks and other phenomena, the back surface chipping is as high as 171.6 µm. The hybrid processing method not only reduces the degree of thermal damage, but also reduces tool wear, and the front surface is flat and clean after cutting, without a chipping phenomenon, and the back surface chipping is only 7.9 µm, which is 20 times lower than the dicing saw method.
REBCO coated conductors: enabling the next generation of tokamak reactors
Authors: Li Xiaodong , Ainslie Mark , Song Dongbin , Yang Wenjiang , Macián-Juan Rafael 
Published: January 2025

Abstract
The discovery of rare-earth barium copper oxide (REBCO) materials with high critical temperatures, and the continued advancements in the fabrication of REBCO coated conductors with extremely high critical current densities, has enabled the development of ultra-high-field (>20 T) compact and large-scale thermonuclear fusion devices. At present, around a dozen global commercial manufacturers are able to supply high-quality REBCO coated conductors with excellent performance. Significant advancements have been made for high-temperature, low-field applications such as motors, generators, long-length transmission cables, and so on using REBCO coated conductors. Nonetheless, multiple ongoing critical challenges under low-temperature, high-field conditions, such as irreversible degradation of the critical current, along with insufficient mechanical protection and inadequate reduction of AC losses, remain unsolved, collectively hindering their utilization in high-field thermonuclear fusion reactors. This paper provides a comprehensive theoretical and technical review of the current state-of-the-art, associated challenges, and prospects in the research and development (R&D) of REBCO coated conductors, cables, and magnet systems for high-field fusion. It highlights the significant enhancements in current-carrying capacity, mechanical protection, and AC loss reduction achieved over the past decade. The paper delves into detailed analyses of potential cabling solutions that offer exceptional current-carrying capacity while ensuring an optimal inductance balance for toroidal, poloidal, and central solenoid coils in tokamak devices. This work endeavours to lay the groundwork for the R&D of the next-generation REBCO magnets to facilitate the construction of ultra-high-field compact and large-scale tokamak reactors.
Distinguishing Majorana bound states from Andreev bound states through differential conductance and current noise spectrum
Authors: Zhao Huajin , Wang Junrong , Mao Hong , Jin Jinshuang 
Published: January 2025

Abstract
We investigate the quantum transport through a quantum dot coupled with a superconducting (SC) nanowire. By elaborating the differential conductance and current noise spectrum, we focus on the distinct characteristics of the topological Majorana bound states (MBSs) and trivial Andereev bound states (ABSs) hosted in SC wire. For MBSs with a topological quality factor q = 1, we observe the degenerate features manifested as the zero-bias peak (ZBP) in differential conductance and the Rabi dips degeneracy (RDD) in noise spectrum. In contrast, for ABSs with q < 1, the splitting of these degenerate features depends on the linewidth, arising from realistic measurement conditions. Furthermore, we identify the critical quality factors

q

c

and

q

S

associated with the emergences of ZBP and RDD, respectively. The value of

q

c

is temperature-dependent, and we establish a suitable temperature window to ensure the visibility of single ZBP in the experiments. Whereas,

q

c

depends on the coupling strength rather than the temperature. Typical values for these quality factors are approximately

q

c

≈
0.93

and

q

S

≈
0.99

. Our results suggest that the degenerate Rabi spectrum signal could serve as a hallmark for the presence of MBSs, which goes beyond the scope of differential conductance.
Effect of combined Kappa-Cairns distributed electrons on modulational instability and envelope soliton of ion-acoustic waves in electron-ion dusty plasma
Authors: Pain Rittika , Dalui Sandip , Sardar Sankirtan , Bandyopadhyay Anup 
Published: January 2025

Abstract
Theoretical and numerical investigations are performed to study the amplitude modulation of ion-acoustic waves in an unmagnetized collisionless dusty plasma system whose components are warm ions (adiabatic), charged (negative) dust particles and Combined Kappa-Cairns distributed electrons. Modulational instability of ion-acoustic waves is analyzed through derivation of the nonlinear Schrödinger equation using the reductive perturbation technique by implementing hydrodynamic equations for this system. The conditions for modulational instability for this electron-ion dusty plasma system have been developed, and the impacts of the relevant physical parameters on the instability region along with the maximum growth rate of instability are demonstrated. Bright and dark envelope solitons are presented, and it is observed that the profiles of envelope solitons are significantly influenced by the existence of high-energy Combined Kappa-Cairns distributed electrons.
A new thermoelectric ECG model: influence of bundle branch block and variations in body temperature
Authors: Pascaline Dongmo Vougmo Inès , Thierry Djoumessi René , Beceau Pelap François , Médard Fogue 
Published: January 2025

Abstract
This work proposes a thermoelectric model to investigate the behavior of specific pathological situation, such as bundle branch block. Impact of temperature is evaluated and its role in controlling the pathology determined. Our proposed 2D thermoelectric model incorporates the heart, lungs, torso, and blood cavities. The Fitzhugh-Nagumo equations that simulate the electrical activity of cardiac myocytes are coupled with temperature equations while considering the parameters of the bundle branch block to analyze their impact on the electrocardiogram. We establish that the presence of bundle branch block significantly affects electrocardiogram morphology, resulting in changes in wave amplitude and interval durations. Moreover, our findings reveal that variations in body temperature alter this pathological condition leading to further distortions in the electrocardiogram. Our thermoelectric model provides valuable insights into the behavior of bundle branch block under temperature variations. This knowledge may potentially contribute to the development of novel treatment and management strategies utilizing thermal control to enhance outcomes for patients presenting similar symptoms.
Influence of axis magnetic field on operation of hall thruster with internally mounted cathode
Authors: Che Xingdong , Zeng Demai , Lian Huibin , Ding Yongjie , Wei Liqiu , Yu Daren , Li Hong 
Published: January 2025

Abstract
Hall thrusters with internal cathodes achieve higher efficiency, smaller plume divergence angles, and improved plume symmetry compared with those with external cathodes. Electrons from the internal cathodes first encounter an axis magnetic field and are coupled with the plasma plume. However, few studies have focused on the influence of axis magnetic field on the operation of Hall thrusters with internally mounted cathodes. Two approaches–applying an additional inner coil and modifying the diameter of the central aperture–are proposed to change the axis magnetic field, and the discharge characteristics are tested. As the number of ampere turns of the additional coil current in-creased, the maximum magnetic-field strength increased by 11%, and the gradient at the exit of the internal cathode decreased by 83%, thus resulting in relative reductions of 0.81% and 1.75% in the thrust and efficiency, respectively, under the rated operating condition. As the diameter of the central aperture decreased, the maximum magnetic strength increased by 9.1% and the gradient at the exit of the cathode increased by 36.3%, thus resulting in relative reductions of 1.88% and 5.71% in the thrust and efficiency, respectively, under the rated condition. Although the performance tendencies are the same, quantitative differences are observed. An analysis of the mechanism indicates that an axis magnetic field with weak strength and a gradual gradient are conducive to electrons traversing down-stream and crossing the magnetic field to couple with the plasma plume. Thus, the differences between the discharge characteristic variations under the two approaches can be explained qualitatively, and guidance is provided for op-timizing the axis magnetic field of Hall thrusters with internal cathodes.
New approach to modeling of thermal electrons heating rate in ionosphere F-layer
Authors: Lu Zhijian , Yao Jingfeng , Aktaev Nurken E , Kudryavtsev A A , Yerzhanov K K , Zhou Zhongxiang , Wang Ying , Li Hui , Wu Jian , Yuan Chengxun 
Published: January 2025

Abstract
Heating rate of thermal electrons by superthermal electrons in ionospheric F-layer at altitudes of 150–350 km was studied over a wide range of zenith angles 45–90 degrees. As a result, a simple and universal formula for calculating the heating rate was obtained. The generalized Hoegy theory was used to obtain the formula. Within the framework of the Hoegy theory, the heating rate is determined by superthermal electrons flux and energy loss function. The energy dependence of the superthermal electron flux was obtained using the bi-exponential function. The kinetic approach was used to receive an analytical expression for the energy loss function. It has been shown that the obtained expression in good agreement with the widely used Swartz approximation. The applicability limits of the obtained expression for energy losses are discussed. It was demonstrated that the heating rate calculations using the formula obtained in the work has a good agreement with the experiments.
Determining oscillator strengths of cesium from magic wavelengths of the D1 line
Authors: Liu Yang , Fan Shaofeng , Liu Wenyuan , Li Yijun , Bai Jiandong 
Published: January 2025

Abstract
A magic-wavelength optical dipole trap (ODT) can eliminate the differential light shift of the transition between atomic states, so that transition frequency between the two states is the same as that in free space, which is of great significance for exploring atomic structure. Here we calculate the dynamic polarizabilities of the 6S1/2 ground state and 6P1/2 excited state of the cesium atom which are connected by the D1 line, by using the relativistic coupled cluster method, and obtain magic wavelengths of ODT laser for trapping the two states simultaneously. By using these magic wavelengths, we calculate oscillator strength of the 6P1/2 → 7D3/2 transition for linearly and circularly polarized lights. Furthermore, we analyze the influence of magic wavelengths on oscillator strengths.
Dual high-Q bound states in the continuum based Fano resonances in bulk WS2 meta-lattice
Authors: Danaeifar Mohammad 
Published: January 2025

Abstract
Bound states in the continuum (BICs) play a promising role in enhancing light–matter interaction with a high quality (Q) factor in transition metal dichalcogenides (TMDCs). In this work, a structured meta-lattice of bulk tungsten disulfide (WS2), a well-known material of TMDCs, with double high-Q resonances governed by quasi-BIC is presented. Two types of quasi-BIC are exploited simultaneously by rotational and longitudinal asymmetries of WS2 rods, acting as the meta-atoms. These Fano line shaped quasi-BIC resonances have a very high quality factor of 1.6 × 104 with a reasonable asymmetric parameter of 1%. Although, tuning the asymmetric parameter changes the linewidth of the resonances and the resulting Q-factor, for all values of these parameters the amplitude of reflection remains constant at one. In addition to exploring and analysing two quasi-BICs, strong coupling between exciton and quasi-BICs is illustrated with Rabi splitting of 116.6 meV and 54.2 meV for rotational and longitudinal asymmetries, respectively. These findings show promise for the development of high-Q photonic devices and applications in polaritonics.
Displacement sensing through deformation of Fano spectral lines from bilayer-grating compound structure
Authors: Qin Xielin , Fang Yun-Tuan 
Published: January 2025

Abstract
In order to achieve the reversal of Fano spectral lines and a new displacement sensing, we construct a compound structure composed of two periodic gratings fixed on two sides of a waveguide layer. Through the analysis on guided mode resonance mechanism and the eigen modes, and the calculation of transport spectra, we have found a deformation and reversal of Fano spectral lines dependent on the translational displacement between the two gratings. We combine deep learning with the deformation of Fano spectral line to design displacement sensors with a nanometer resolution.
Design, implementation of six-dimensional chaotic system and its application in color image encryption
Authors: Lv Jiliang , Xie Qinggang , Zhang Jie 
Published: January 2025

Abstract
A six-dimensional chaotic system is constructed by introducing nonlinear functions. Additionally, the system proposed is confirmed through analog circuits and field-programmable gate arrays (FPGA) digital circuits. A double-block encryption algorithm is proposed that combines the improved 2D Logistic mapping with the six-dimensional chaotic system proposed to perform DNA computation on image pixels, achieving a ‘one image, one key’ effect for secure and efficient encryption of images.
Theoretical study of a novel optical biosensor using a structurally chiral medium based on the Kretschmann configuration for the detection of cancer cells
Authors: Ghorani Nadia , Madani Amir , Entezar Samad Roshan 
Published: January 2025

Abstract
In this study, a high-precision optical biosensor composed of a structurally chiral medium (SCM) with

4
¯

2
m

point group symmetry and an aluminum metallic layer has been theoretically investigated using the Kretschmann configuration for cancer cell detection. For numerical analysis, the

4
×
4

transfer matrix method was employed to derive the absorption spectrum of the structure when subjected to p-polarized incident waves. The results indicate that two modes, surface plasmon polaritons (SPPs) and waveguide modes, can be excited at the metal-SCM interface. Our findings suggest that due to the minimal penetration of SPPs as an evanescent wave into the biosample region, waveguide modes are more advantageous for sensor applications. Furthermore, the resonance angle of the waveguide modes exhibits high sensitivity to the biosample’s refractive index, enhancing the biosensor’s functionality. Additionally, How the SCM layer tilt angle has been investigated, denoted as

χ

, affects the absorption peaks and the biosensor’s efficiency. Optimal performance was achieved

χ
=

30

°

, although optimal sensor parameters vary across different biosample types.
Application of a random forest algorithm that considers barometric pressure in GNSS-R sea surface wind speed retrieval
Authors: Ma Yi , Wang Yifan , Wang Guofang , Geng Hao , Chen Yuan 
Published: January 2025

Abstract
This paper aims to rely on CYGNSS data to propose a random forest-based wind speed retrieval method that considers barometric pressure as a pivotal factor. Taking the Hawaiian Islands and the peripheral waters as the subject, the research conducts a systematic analysis of the spatial-temporal variation characteristics of wind speeds. In this case, an innovative random forest (RF) model that considers barometric pressure is built and trained, with the longitude, latitude, time, normalized bistatic radar scattering cross section (NBRCS), leading-edge slope (LES), and barometric pressure data as the input features, and the measured buoy wind speeds as the target variable. The results show that the introduction of barometric pressure can significantly improve the accuracy of wind speed retrieval, raising the correlation to above 0.8 and reducing the root mean square error (RMS) by more than 40%. The RF (pressure) method performs best when the pressure system changes dynamically, such as in winter. In the Hawaiian Islands, moreover, the wind speeds exhibit notable spatial variations across seasons. The wind speeds are generally stable and moderate in spring and autumn. In winter, the wind speeds in the northern and northwestern regions can reach the highest level. In summer, the wind speeds in the southeastern region come to a significant decrease. These findings reveal the complex influences of barometric gradients like the subtropical high and the Aleutian Low, as well as topography and ocean currents, on wind speeds, providing a scientific basis for understanding regional climatic dynamics and wind energy resource development.
Contact value theorem for electric double layers with modulated surface charge density
Authors: Šamaj Ladislav 
Published: January 2025

Abstract
The contact value theorem was originally derived for Coulomb fluids of mobile charged particles in thermal equilibrium, in the presence of interfaces carrying a uniform surface charge density and in the absence of dielectric discontinuities. It relates the pressure (the effective force) between two parallel electric double layers (EDLs) to the particle number density and the surface charge density at the interface, separately for each of the two EDLs. In this paper, we generalise the contact value theorem to EDLs with interfaces carrying a modulated surface charge density. The derivation is based on balance of forces exerted on interfaces. The relevance of particular terms of the contact value theorem is tested on an exactly solvable two-dimensional Coulomb system with counterions only at the coupling constant

Γ
=
2

.