bluuebunny/crossref_metadata_2025_split huggingface dataset:
Elucidating the coherent and incoherent reflection of plane-waves in finite thickness media: a practical pedagogical application
Authors: Villegas Cesar E P , Romero-Abad David , Rojas Wudmir Y 
Published: March 2024

Abstract
The propagation of light through a thin film interfaced between two semi-infinite media serves as a compelling illustration for elucidating electromagnetic wave interactions with matter at the undergraduate level. Despite its pedagogical significance and diverse technological applications, this model often receives inadequate attention in foundational electromagnetism literature, limiting early student exposure to this emblematic concept. In this pedagogical initiative, we present a comprehensive analysis of electromagnetic wave propagation through a dielectric medium positioned between semi-infinite media. We examine interference phenomena arising from back-and-forth reflected waves within the dielectric, focusing on the coherent and incoherent reflection regimes as limiting cases. Employing rigorous analytical treatment, we delineate transmittance and reflectance profiles, offering students a lucid understanding of how the refractive index’s real and imaginary components compete and manifest under specific conditions. This analytical approach enhances students’ comprehension of electromagnetic wave behavior within diverse mediums. Furthermore, we extend this theoretical foundation to practical applications, emphasizing renewable energy contexts. By calculating absorptance, we estimate the maximum photo-generated current and power conversion efficiency of a prototype solar cell, establishing a tangible link between theoretical knowledge and real-world solar energy utilization.
Inverse spectral problem for the Schrödinger operator on the square lattice
Authors: Wu Dongjie , Yang Chuan-Fu , Bondarenko Natalia Pavlovna 
Published: March 2024

Abstract
We consider an inverse spectral problem on a quantum graph associated with the square lattice. Assuming that the potentials on the edges are compactly supported and symmetric, we show that the Dirichlet-to-Neumann map for a boundary value problem on a finite part of the graph uniquely determines the potentials. We obtain a reconstruction procedure, which is based on the reduction of the differential Schrödinger operator to a discrete one. As a corollary of the main results, it is proved that the S-matrix for all energies in any given open set in the continuous spectrum uniquely specifies the potentials on the square lattice.
Plasmonic gas sensors based on nanomaterials: mechanisms and recent developments
Authors: Vaidyanathan Antara , Mondal Brinti , Rout Chandra Sekhar , Chakraborty Brahmananda 
Published: March 2024

Abstract
Sensing devices for rapid analytics are important societal requirements, with wide applications in environmental diagnostics, food testing, and disease screening. Nanomaterials present excellent opportunities in sensing applications owing to their superior structural strength, and their electronic, magnetic, and optoelectronic properties. Among the various mechanisms of gas sensing, including chemiresistive sensors, electrochemical sensors, and acoustic sensors, another promising area in this field involves plasmonic sensors. The advantage of nanomaterial-plasmonic sensors lies in the vast opportunities for tuning the sensor performance by optimizing the nanomaterial structure, thereby producing highly selective and sensitive sensors. Recently, several novel plasmonic sensors have been reported, with various configurations such as nanoarray resonator-, ring resonator-, and fibre-based plasmonic sensors. Going beyond noble metals, some promising nanomaterials for developing plasmonic gas sensor devices include two-dimensional materials, viz. graphene, transition metal dichalcogenides, black phosphorus, blue phosphorus, and MXenes. Their properties can be tuned by creating hybrid structures with layers of nanomaterials and metals, and the introduction of dopants or defects. Such strategies can be employed to improve the device performance in terms of its dynamic range, selectivity, and stability of the response signal. In this review, we have presented the fundamental properties of plasmons that facilitate its application in sensor devices, the mechanism of sensing, and have reviewed recent literature on nanomaterial-based plasmonic gas sensors. This review briefly describes the status quo of the field and prospects.
Recent advances in in-sensor computational vision sensors: from mechanisms to applications
Authors: Xu Hang , Meng Leixin , Guo Yiyu , Tang Wenhao , Huang Liangliang , Dai Tiantian , Liu Xu , Yang Qing 
Published: March 2024

Abstract
The number of vision sensors continues to increase with the rapid development of intelligent systems. The effective transmitting and processing of the sensing data become difficult due to the sensing, computing and memory units being physically separated. In-sensor computing architecture inspired by biological visual systems with efficient information processing has attracted increasing attention for overcoming these performance limitations. Bipolar cells in the retina can generate ON/OFF information processing channels to amplify marginal information. The synaptic structure is plastic and can enhance the output information that is repeated many times. In recent years, numerous new material and device strategies to implement in-sensor computing by mimicking the functions of bipolar cells and synapses have been reported: ON/OFF optical responses have been realized on two-dimensional materials by band-modulation and tunneling; synaptic responses, such as short-term plasticity and long-term plasticity, have been realized by phase transition and carrier regulating. In this review, we will summarize the biological vision processes, analyse the physical mechanisms behind the in-sensor computational vision sensors (ICVSs), and then overview the emerging physical artificial neural networks implemented with ICVSs. After that, we will discuss ICVS design based on biological mechanisms beyond ON/OFF bipolar-cell-response and synaptic response.
The modulation of perpendicular magnetic anisotropy and spin–orbit toque in Pt/Co/Pt multilayers with interfacial decoration by insertion of a Bi layer
Authors: Wu Yong , Wen Kaibin , Zhang Tanzhao , Liu Ye , Meng Kangkang , Xu Xiaoguang , Jiang Yong 
Published: March 2024

Abstract
Bismuth is a well-known semimetal material with strong spin–orbit coupling and has been confirmed to exhibit a larger spin Hall angle in CuBi and PtBi alloys with low Bi-doping concentration. In this study, we investigated perpendicular magnetic anisotropy (PMA) and spin–orbit torques (SOTs) in Pt/Co/Pt multilayers by inserting a Bi layer with a thickness of 2 nm at the Co/Pt interface. Two types of PMA multilayers, Pt (3 nm)/Co (1 nm)/Pt (5 nm) and Pt (3 nm)/Co (1 nm)/Pt (1 nm), with different spin accumulations, were designed and prepared by varying the top Pt thickness. A significant enhancement of PMA and SOT efficiency is observed in the Pt (3 nm)/Co (1 nm)/Bi (2 nm)/Pt (5 nm) multilayer via a Bi-layer interfacial decoration. However, for the Pt (3 nm)/Co (1 nm)/Bi (2 nm)/Pt (1 nm) multilayers, both PMA and SOT efficiency decrease with decoration of the Bi layer at the Co/Pt interface. Meanwhile, the sign of SOTs changes in the Pt (3 nm)/Co (1 nm)/Pt (5 nm) and Pt (3 nm)/Co (1 nm)/Pt (1 nm) multilayers when introducing a Bi layer. This completely opposite behavior illustrates that the Bi/Pt interface plays an important role in modulating the PMA and SOT efficiency of Pt/Co/Bi/Pt multilayers. Optimizing the alloying of Bi/Pt could be an effective approach to increase the PMA and SOT efficiency of Pt/Co/Bi/Pt multilayers.
Ultra-sensitive fiber optic sensor for glucose concentration measurement based on Vernier effect in cascaded Mach–Zehnder interferometers
Authors: Zhang Sa , Chen Hailiang , Fan Xiaoya , Li Hongwei , Li Lida , Shi Ruyue , Gu Mingqi , Li Shuguang 
Published: March 2024

Abstract
In this paper, a fiber optic glucose concentration sensor based on cascaded Mach–Zehnder interferometers (CMZIs) was proposed and experimentally verified. Two single-mode fibers (SMFs) with slightly different tapering lengths and as well free spectral ranges (FSRs) were obtained through the melt-drawn cones technique and then were cascaded together to achieve the Vernier effect (VE). Experimental results showed that the measurement sensitivity of glucose concentration based on a single tapered SMF was 0.0494 nm (mmol l−1)−1. Furthermore, the measurement sensitivity based on the cascaded tapered SMFs was enhanced by 4.86 times to an ultra-high level of 0.2402 nm (mmol l−l)−1. The resolution reached 0.083 mmol l−1. The refractive index sensitivity reached 9066 nm/RIU. The resolution reached 2.21 × 10−6 RIU. In addition, the proposed glucose concentration sensor based on CMZIs shows good hysteresis. In conclusion, the designed sensor, showing the merits of easy to fabricate, high sensitivity, and high detection resolution, could be used to monitor the tiny variation in glucose concentration.
Klein–Gordon particles in a quasi-pointlike global monopole spacetime and a Wu-Yang magnetic monopole: invariance and isospectrality
Authors: Mustafa Omar 
Published: March 2024

Abstract
We use two correlated metric functions and transform/deform the pointlike global monopole (PGM) spacetime metric into a quasi-PGM (QPGM) spacetime one. We study Klein–Gordon (KG) particles (manifestly introduced by the non-minimal coupling form of the operator

D

˜

μ

=

D

μ

+

F

μ

, with

F

μ

∈

R

, and D

μ
= ∂
μ
− ie
A

μ
) in such QPGM spacetime background. We show that the KG-particles in the QPGM spacetime are isospectral and invariant with KG-particles in the PGM spacetime, provided that the two metric functions are correlated. The Wu-Yang magnetic monopole (WYMM) is also included in the process. We report the effects of both monopoles PGM/QPGM and WYMM on the spectroscopic structure of two models, KG-oscillators and KG-Coulomb particles in such spacetime background. Moreover, we discuss KG-Coulomb particles and shifted KG-oscillators in a PGM spacetime and a WYMM, where such models are manifestly introduced by some Lorentz scalar interaction potentials S(r). The current study is not only of fundamental observability nature but also of pedagogical interest in quantum gravity.
Magnetic exchange interactions at the proximity of a superconductor
Authors: Aceves Rodriguez Uriel A , Guimarães Filipe , Brinker Sascha , Lounis Samir 
Published: March 2024

Abstract
Interfacing magnetism with superconductivity gives rise to a wonderful playground for intertwining key degrees of freedom: Cooper pairs, spin, charge, and spin–orbit interaction, from which emerge a wealth of exciting phenomena, fundamental in the nascent field of superconducting spinorbitronics and topological quantum technologies. Magnetic exchange interactions (MEIs), being isotropic or chiral such as the Dzyaloshinskii–Moriya interactions, are vital in establishing the magnetic behavior at these interfaces as well as in dictating not only complex transport phenomena, but also the manifestation of topologically trivial or non-trivial objects. Here, we propose a methodology enabling the extraction of the tensor of MEI from electronic structure simulations accounting for superconductivity. We apply our scheme to the case of a Mn layer deposited on Nb(110) surface and explore proximity-induced impact on the MEI. The latter are weakly modified by a realistic electron-phonon coupling. However, tuning the superconducting order parameter, we unveil potential change of the magnetic order accompanied with chirality switching, as induced by the interplay of spin-orbit interaction and Cooper pairing. Owing to its simple formulation, our methodology can be readily implemented in state-of-the-art frameworks capable of tackling superconductivity and magnetism. We thus foresee implications in the simulations and prediction of topological superconducting bits as well as of cryogenic superconducting hybrid devices involving magnetic units.
Features extraction of point clouds based on Otsu’s algorithm
Authors: He Yibo , Hu Zhenqi , Wang Rui , Zhu Haizhong , Fu Guilin 
Published: March 2024

Abstract
Currently, a point cloud extraction method based on geometric features requires the configuration of two essential parameters: the neighborhood radius within the point cloud and the criterion for feature threshold selection. This article addresses the issue of manual selection of feature thresholds and proposes a feature extraction method for 3D point clouds based on the Otsu algorithm. Firstly, the curvature value of each point cloud is calculated based on the r-neighborhood of the point cloud data. Secondly, the Otsu algorithm is improved by taking the curvature values as input for the maximum inter-class variance method. The optimal segmentation threshold is obtained based on the Otsu algorithm to divide the point cloud data into two parts. Point cloud data whose curvature is greater than or equal to the threshold is extracted as feature point data. In order to verify the reliability of the algorithm presented in this paper, a method for accuracy assessment of regular point cloud data is proposed. Additionally, comparative analysis was conducted on data with varying point cloud densities and on data contaminated with Gaussian white noise using multiple methods. Experimental results show that the proposed algorithm achieves good extraction results for data with 90% simplification rate and low noise.
Power transformer fault diagnosis using dynamic multiscale graph modeling and M2SGCN network based on statistical fusion
Authors: Liu Xiaoyan , He Yigang 
Published: March 2024

Abstract
Power equipment fault diagnostics hold significant importance for the stability of power grid systems. In pursuit of this objective, this paper proposes a fault diagnosis method that utilizes dynamic multiscale graph (DMG) modeling and the multiscale multi-stream GCN(M2SGCN) network, incorporating statistical fusion. Specifically, a novel DMG modeling method is proposed to derive visibility graph data and horizontal visibility graph data from vibration signals across multiple scales. Next, a comprehensive neural network architecture named M2SGCN is established to learn global and local features simultaneously, providing a more precise representation. Subsequently, a Dempster Shafer evidence theory statistical fusion technique combined with an adaptive threshold model (DSTFusion) is utilized to integrate primary decision results for enhanced fault diagnosis accuracy. In addition, two datasets obtained from single-phase and three-phase power transformers are analyzed to demonstrate the evolution process. When compared to state-of-the-art indicators such as accuracy, precision, recall, and F1 scores, the method proposed excels in multiple aspects, successfully detecting fault states before their occurrence and achieving outstanding performance.
Modeling and simulation of anisotropic cross-linked cellulose fiber networks with an out-of-plane topography
Authors: Agarwal Shubham , Green Sheldon I , Phani A Srikantha 
Published: March 2024

Abstract
Non-woven cellulose fiber networks of low areal density are widely used in many industrial applications and consumer products. A discrete element method (DEM) modeling framework is advanced to simulate the formation of strongly anisotropic cellulose fiber network sheets in the dilute limit with simplified hydrodynamic and hydroelastic interactions. Our modeling accounts for in-plane fiber orientation and viscous drag indirectly by using theories developed by Niskanen (2018 Fundamentals of Papermaking, Trans. 9th Pulp and Paper Fundamental Research Symp. Cambridge, 1989 (FRC) pp 275–308) and Cox (1970 J. Fluid Mech.
44 791–810) respectively. Networks formed on a patterned and flat substrate are simulated for different fiber types, and their tensile response is used to assess the influence of the out-of-plane topographical pattern, specifically, on their stiffness and strength. Sheets with the same grammage and thickness, but composed with a higher fraction of softwood fiber (longer fibers with large diameter), have higher strength and higher strain to failure compared to sheets made from hardwood fibers (short fibers with small diameter). However, varying the fiber fraction produces only an insignificant variation in the initial sheet stiffness. The above simulation predictions are confirmed experimentally for sheets comprised of fibers with different ratios of Eucalyptus kraft and Northern Bleached Softwood Kraft fibers. Sheets with out-of-plane topography show an unsymmetric mass distribution, lower tensile stiffness, and lower tensile strength compared to those formed on a flat substrate. The additional fiber deformation modes activated by the out-of-plane topography, such as bending and twisting, explain these differences in the sheet mechanical characteristics.
The composition effect on the structural and thermodynamic properties of Cu–Ag–Au ternary nanoalloys: a study via molecular dynamics approach
Authors: Cuba-Supanta Gustavo , Amao P , Quispe-Huaynasi F , Pinto-Vergara M Z , Pacheco Elluz , Flores S Y , Soncco C , Loaiza-Tacuri V , Rojas-Tapia J 
Published: March 2024

Abstract
Metal ternary nanoalloys or trimetallic nanoparticles have emerged, in recent years, as novel and relevant materials in different fields due to the synergy of three metals in a single system that leads to unique physicochemical properties as compared to mono- and bimetallic nanoparticles. In this study, the influence of composition on the structural and thermodynamic properties of Cu–Ag–Au nanoalloys with 5083 atoms is analyzed using molecular dynamics simulations. Relevant thermodynamic quantities are used to describe the melting and solidification behaviors of three models of Cu–Ag–Au nanoalloys. Our results indicate that the melting temperature presents linear and quadratic dependencies with the composition, i.e. for Cu33Ag

67
−
x

Au
x
, Ag33Cu

67
−
x

Au
x
, and Au33Ag

67
−
x

Cu
x
are

T
m

=
912.6
+
1.9
x

,

T
m

=
882.3
+
2.7
x

, and

T
m

=
1056.6
−
4.9
x
+
0.07

x
2

, respectively. In addition, most Ag atoms segregate to the surface and the Au and Cu atoms are localized in the center of the nanoalloy during the heating process, and this trend is maintained in the cooling process. The solidification temperature does not have an explicit correlation with the composition. Furthermore, the structural analysis of cooled nanoalloys exhibits local FCC and HCP symmetries, and the excess energy shows that Cu33Ag27Au40, Au33Ag17Cu50, and Ag33Cu37Au30 are relatively more stable to form nanoalloys. Finally, the possibility of controlling the composition in these metal nanoalloys opens up potential applications in plasmonic, catalysis, and bactericidal (by Ag surface segregation) fields.
Advances in selenium from materials to applications
Authors: Liu Hao , Chen Liping , Shen Yunkun , Fan Li , Zhang Jiawei , Zhu Hongliang , Shi Yi , Yan Shancheng 
Published: March 2024

Abstract
Over the past few decades, single-element semiconductors have received a great deal of attention due to their unique light-sensitive and heat-sensitive properties, which are of great application and research significance. As one promising material, selenium, being a typical semiconductor, has attracted significant attention from researchers due to its unique properties including high optical conductivity, anisotropic, thermal conductivity, and so on. To promote the application of selenium nanomaterials in various fields, numerous studies over the past few decades have successfully synthesized selenium nanomaterials in various morphologies using a wide range of physical and chemical methods. In this paper, we review and summarise the different methods of synthesis of various morphologies of selenium nanomaterials and discuss the applications of different nanostructures of selenium nanomaterials in optoelectronic devices, chemical sensors, and biomedical applications. Finally, we discuss possible challenges for selenium nanodevices and provide an outlook on the future applications of selenium nanomaterials.
Surface termination modulation for superior S-Scheme Bi2WO6/BiOI heterojunction photocatalyst: a hybrid density functional study
Authors: Nie Hongwei , Liu Zuoyin , Kong Bo , Xu Xiang , Wang Wentao 
Published: March 2024

Abstract
The prevailing theoretical frameworks indicate that depending on the growth conditions, the Bi2WO6(001) surface can manifest in three distinct terminations—DL-O–Bi (DL: double layers), O–Bi, and O–W. In this study, we conduct a comprehensive examination of the interplay between these terminations on Bi2WO6(001) and the 1I-terminated BiOI(001) facet, especially focusing on their impact on the photocatalytic activity of Bi2WO6/BiOI heterostructure, applying hybrid functional calculations. The models formulated for this research are designated as Bi2WO6(O–Bi)/BiOI(1I), Bi2WO6(DL-O–Bi)/BiOI(1I), and Bi2WO6(O–W)/BiOI(1I). Our findings reveal that Bi2WO6(O–Bi)/BiOI(1I) shows a type II band alignment, which facilitates the spatial separation of photo-generated electrons and holes. Notably, the Bi2WO6(DL-O–Bi)/BiOI(1I) configuration has the lowest binding energy and results in an S-scheme (or Step-scheme) heterostructure. In contrast to the type II heterostructure, this particular configuration demonstrates enhanced photocatalytic efficiency due to improved photo-generated carrier separation, augmented oxidation capability, and better visible-light absorption. Conversely, Bi2WO6(O–W)/BiOI(1I) presents a type I projected band structure, which is less conducive for the separation of photo-generated electron–hole pairs. In summation, this investigation points out that one could significantly refine the photocatalytic efficacy of not only Bi2WO6/BiOI but also other heterostructure photocatalysts by modulating the coupling of different terminations via precise crystal synthesis or growth conditions.
Formation of singularities in plasma ion dynamics
Authors: Bae Junsik , Choi Junho , Kwon Bongsuk 
Published: March 2024

Abstract
We study the formation of singularity for the Euler–Poisson system equipped with the Boltzmann relation, which describes the dynamics of ions in an electrostatic plasma. In general, it is known that smooth solutions to nonlinear hyperbolic equations fail to exist globally in time. We establish criteria for C
1 blow-up of the Euler–Poisson system, both for the isothermal and pressureless cases. In particular, our blow-up condition for the pressureless model does not require that the gradient of velocity is negatively large. In fact, our result particularly implies that the smooth solutions can break down even if the gradient of initial velocity is trivial. For the isothermal case, we prove that smooth solutions leave C
1 class in a finite time when the gradients of the Riemann functions are initially large.