bluuebunny/crossref_metadata_2025_split huggingface dataset:
A versatile setup for hydrogen isotope permeation studies
Authors: Sand P. , Manhard A. , von Toussaint U. 
Published: December 2024

The Testbed for Analysis of Permeation of Atoms in Samples (TAPAS) is an experimental setup for ion-driven permeation studies with a focus on investigating wall materials for nuclear fusion devices. A monoenergetic, mass-filtered high-intensity keV ion beam is focused and directed onto the permeation sample by electrostatic ion optics and decelerated to the desired ion energy by a dedicated set of apertures close to the sample. We were able to obtain ion energies as low as 170 eV/D with a D3+ ion beam with an ion flux density of the order of 1020 D/m2s on a beam-wetted area of ∼33 mm2. These conditions avoid sputtering of W targets by the ion beam and are representative of the particle flux and energy spectrum impinging on the first wall of a prospective nuclear fusion power reactor. Permeation samples can be heated up to 1000 K in an ultra-high vacuum. The design of the deceleration system, together with a high pumping speed in the loading chamber, ensures a low pressure of recycling hydrogen isotope molecules in front of the sample. In addition to ion-driven permeation, TAPAS provides a limited capability for gas-driven permeation at low pressures up to nearly 1 mbar. Permeating hydrogen isotopes are detected with a quadrupole mass spectrometer in the downstream ultra-high vacuum chamber. After a detailed description of the setup and calibration procedures for implanted particle flux, mass spectrometer, and neutral gas pressure, benchmark experiments on recrystallized, 50 μm thick tungsten foils are shown, demonstrating that diffusion-limited boundary conditions for permeation were reached.
Structural changes in honeycomb layers of Mn3NiTa2O9 under pressures up to 14 GPa using in situ synchrotron x-ray diffraction
Authors: Singh H. , Seehra M. S. , Irshad K. A. , Joseph B. , Prellier W. , Thota S. 
Published: December 2024

Changes in the structural parameters of trigonal honeycomb layers of Mn3NiTa2O9 are reported under pressures up to 14 GPa by in situ synchrotron x-ray diffraction employing a diamond anvil cell with a 4:1 methanol–ethanol mixture as the pressure transmitting medium (PTM). The lattice parameters a, c, the ratio c/a, and the volume V of the unit cell all decrease almost linearly with an increase in pressure P up to a critical pressure PC = 9.2 GPa. The fit of the V vs P data for P &lt; PC to the expression for the equation of state yields the bulk modulus = 144.5 GPa for the trigonal Mn3NiTa2O9. For P &gt; PC, the widths of the Bragg lines increase, and their intensities decrease rapidly. By employing the Williamson–Hall analysis of the linewidths, the observed changes above P &gt; PC can be interpreted as due to rapidly increasing strain together with a decrease in the effective micro-crystallite size D. However, at this critical pressure, the hydrostatic conditions change due to the solidification of the PTM. The observed significant effects on the broadening of the Bragg lines and their rapid intensity reduction, together with an increasing trend seen in the lattice parameter, may be due to interstitial defects produced by shear stress (as a result of non-hydrostaticity) present for P &gt; PC with the parameter D reflecting mean defect-free distance.
Superconductivity in Medium-Entropy Alloys: Nb2TiW and Nb2TiMo
Authors: Li 李 Kuan 宽 , Chen 陈 Cui-Qun 翠群 , Zeng 曾 Lingyong 令勇 , Li 李 Longfu 龙夫 , Chen 陈 Rui 睿 , Yu 余 Peifeng 沛峰 , Wang 王 Kangwang 康旺 , Xiang 项 Zaichen 载琛 , Yao 姚 Dao-Xin 道新 , Luo 罗 Huixia 惠霞 
Published: December 2024

Abstract
This paper describes the synthesis and characterization of Nb2TiW and Nb2TiMo medium-entropy alloys (MEAs). The Nb2TiW and Nb2TiMo MEAs were successfully synthesized using the arc-melting method. Their structures and superconducting properties were investigated through detailed characterization using X-ray diffraction (XRD), resistivity, magnetization, and specific heat measurements. The XRD results confirmed that the obtained Nb2TiW and Nb2TiMo compounds have the same body-centered cubic (BCC) structure and crystallized in the

I
m

3
¯

m

space group (number 229). Experimental results showed that the superconducting transition temperatures (T
cs) of Nb2TiW and Nb2TiMo are approximately 4.86 and 3.22 K, respectively. The upper and lower critical fields of Nb2TiW are 3.52(2) T and 53.36(2) Oe, respectively, and those of Nb2TiMo are 2.11(2) T and 68.23(3) Oe, respectively. First-principles calculations revealed that the d electrons of Nb, Ti, and Mo or W are the dominant contributors to the density of states near the Fermi level. Specific heat measurement results indicated that Nb2TiW and Nb2TiMo exhibit BCS full-gap s-wave superconductivity.
A Stochastic iteratively regularized Gauss–Newton method
Authors: Bergou Elhoucine , Chada Neil K , Diouane Youssef 
Published: December 2024

Abstract
This work focuses on developing and motivating a stochastic version of a wellknown inverse problem methodology. Specifically, we consider the iteratively regularized Gauss–Newton method, originally proposed by Bakushinskii for infinite-dimensional problems. Recent work have extended this method to handle sequential observations, rather than a single instance of the data, demonstrating notable improvements in reconstruction accuracy. In this paper, we further extend these methods to a stochastic framework through mini-batching, introducing a new algorithm, the stochastic iteratively regularized Gauss–Newton method (SIRGNM). Our algorithm is designed through the use randomized sketching. We provide an analysis for the SIRGNM, which includes a preliminary error decomposition and a convergence analysis, related to the residuals. We provide numerical experiments on a 2D elliptic partial differential equation example. This illustrates the effectiveness of the SIRGNM, through maintaining a similar level of accuracy while reducing on the computational time.
Dynamic thresholding algorithm with memory for linear inverse problems
Authors: Sun Zhong-Feng , Zhao Yun-Bin , Zhou Jin-Chuan , Huang Zheng-Hai 
Published: December 2024

Abstract
The relaxed optimal k-thresholding pursuit (ROTP) is a recent algorithm for linear inverse problems. This algorithm is based on the optimal k-thresholding technique which performs vector thresholding and error metric reduction simultaneously. Although ROTP can be used to solve small to medium-sized linear inverse problems, the computational cost of this algorithm is high when solving large-scale problems. By merging the optimal k-thresholding technique and iterative method with memory as well as optimization with sparse search directions, we propose the so-called dynamic thresholding algorithm with memory (DTAM), which iteratively and dynamically selects vector bases to construct the problem solution. At every step, the algorithm uses more than one or all iterates generated so far to construct a new search direction, and solves only the small-sized quadratic subproblems at every iteration. Thus the computational complexity of DTAM is remarkably lower than that of ROTP-type methods. It turns out that DTAM can locate the solution of linear inverse problems if the matrix involved satisfies the restricted isometry property. Experiments on synthetic data, audio signal reconstruction and image denoising demonstrate that the proposed algorithm performs comparably to several mainstream thresholding and greedy algorithms, and it works faster than the ROTP-type algorithms especially when the sparsity level of signal is relatively low.
Mo-doped vanadium oxide for p-type silicon solar cells with an improved hole selective contact
Authors: Wu Yue , Wang Tao , Liu Dan , Liu Wuqi , Wei Yaju , Fu Wang , Yu Guoqiang , Wang Peng , Cui Can 
Published: December 2024

Abstract
As a typical transition metal oxide with high work function, vanadium oxide (V2O5) is a very promising hole selective layer for efficient crystalline silicon (c-Si) solar cells. The holes are extracted or transported via band-to-band tunneling and trap-assisted tunneling (TAT), which strongly depend on the concentration of oxygen vacancies (V
O); however, very little work has focused on its effective modulation. Herein, solution-processed V2O5 films are doped with Mo6+ to tune the hole selectivity for p-Si heterojunction solar cells. With an appropriate doping concentration of 10 mol%, the surface passivation is improved and the contact resistivity decreases simultaneously. The enhanced hole-selective transport with the dominated TAT mechanism contributes to the photoelectric conversion efficiency (PCE) of V2O5/p-Si heterojunction solar cells being increased from 16.2% to 17.7%, due to the increase of V
O induced by the electron transfer from Mo6+ to V5+. The utilization of forming gas annealing further improves the PCE up to 18.2%, ascribed to the generation of more V
O and the additional passivation of hydrogen, which is the highest achieved with solution-processed V2O5−X
for c-Si heterojunction solar cells up to now.
Current, thrust, and power of a corona discharge plasma thruster at tropospheric altitude
Authors: Grosse Sylvain , Benard Nicolas , Moreau Eric 
Published: December 2024

Abstract
Recent developments in electro-aerodynamics (EAD) thrusters that use plasma have demonstrated their abilities for aircraft propulsion, at least for low-velocity drones. Further improvements in the technology bring EAD propulsion closer to full-scale applications. However, certain doubts still exist concerning their behavior in different atmospheric conditions. The study focuses on the effects of altitude on the propulsive performance of a corona discharge thruster in the troposphere. A thruster is placed in a climatic chamber that can vary the temperature and pressure independently, and force and current measurements provide the thrust generation and power consumption of the thruster. First, tests under varying pressure between 500 and 1000 hPa were performed at room temperature. As expected, at constant voltage, they highlight that the power increases almost linearly when the pressure decreases. Conversely, they demonstrated that the thrust decreases with pressure at a constant current. The combined effects result in a loss of effectiveness (i.e. thrust-to-power ratio) when the pressure reduces. Yet, a plateau of maximum effectiveness is achieved between 800 and 1000 hPa. Secondly, the temperature was varied between −20 °C and +30 °C at ground pressure. No significant effect was captured concerning the current and power, and a weak decrease in thrust was measured at higher temperatures. Finally, altitudes between 0 and 6 km were simulated by combining pressure and temperature modifications. Mostly led by the pressure drop, the power decreases linearly when the altitude increases, but the thrust decreases to a plateau between 3 and 6 km. Hence, the effectiveness also decreases with altitude down to a stagnation between 3 and 6 km. The coupled decreases in drag and thrust with altitude engender a small decrease in the maximum achievable freestream velocity of the thruster down to a plateau over 3 km.
Solution grown quantum dots for quantum science
Authors: Roy Parna , Gogoi Parineeta , Pandey Anshu 
Published: December 2024

Abstract
Solution grown quantum dots (QD) are promising materials for photonic quantum science. These materials are strongly confined and further offer advantages in terms of customizability and scalability. In this review we describe the applications of these materials towards quantum science particularly as single photon emitters. We further compare the progress made towards realizing and functionalizing these materials with the current state of the art in epitaxially grown QDs. We particularly focus on charge injection to regulate electronic energy levels and optical emission, as well as effects of strain that are crucial for quantum information applications. This suggests several potential areas where the physical properties of these materials need to be better understood and controlled to fully realize their potential in quantum science. This article thus summarizes the state of the art in terms of solution grown QD development for quantum science and also outlines key areas where progress is expected before these materials become as developed as their solid-state counterparts.
Radial mechanical properties of deoxyribonucleic acid molecules
Authors: Wang Xia , Dong Jianjun , Gao Mingyan , Wang Ying , Hou Fengyan , Wang Jingyu , Li Ye , Wang Zuobin 
Published: December 2024

Abstract
Given the small diameter of deoxyribonucleic acid (DNA), the difficulty in studying its radial mechanical properties laid in the challenge of applying a precise and controlled small force. In this work, the radial mechanical properties of DNA were measured in the AFM. DNA adhesion properties were analyzed through force-distance curves and adhesion images. The adhesion force values applied on DNA obtained from the force-distance curves were consistent with those obtained from the adhesion images. The Young’s modulus of DNA was determined by collecting the data of indentation depth and the force applied on DNA and using the Hertz model for calculation. At the same compression speed, the Young’s moduli increased with increasing forces, but exhibited a nonlinear growth. This reflected the complex stress–strain behavior of DNA. The impact of speeds on mechanical properties of DNA was explored. Higher speed resulted in greater Young’s moduli and adhesion. This study not only deepens the understanding the mechanical properties of DNA, but also provides a strategy for investigating the mechanical properties of other thin and soft materials.
Mapping indefinite causal order processes to composable quantum protocols in a spacetime
Authors: Salzger Matthias , Vilasini V 
Published: December 2024

Abstract
Formalisms for higher order quantum processes provide a theoretical formalisation of quantum processes where the order of agents’ operations need not be definite and acyclic, but may be subject to quantum superpositions. This has led to the concept of indefinite causal structures (ICS) which have garnered much interest. However, the interface between these information-theoretic approaches and spatiotemporal notions of causality is less understood, and questions relating to the physical realisability of ICS in a spatiotemporal context persist despite progress in their information-theoretic characterisation. Further, previous work suggests that composition of processes is not so straightforward in ICS frameworks, which raises the question of how this connects with the observed composability of physical experiments in spacetime. To address these points, we compare the formalism of quantum circuits with quantum control of causal order (QC-QC), which models an interesting class of ICS processes, with that of causal boxes, which models composable quantum information protocols in spacetime. We incorporate the set-up assumptions of the QC-QC framework into the spatiotemporal perspective and show that every QC-QC can be mapped to a causal box that satisfies these set up assumptions and acts on a Fock space while reproducing the QC-QC’s behaviour in a relevant subspace defined by the assumptions. Using a recently introduced concept of fine-graining, we show that the causal box corresponds to a fine-graining of the QC-QC, which unravels the original ICS of the QC-QC into a set of quantum operations with a well-defined and acyclic causal order, compatible with the spacetime structure. Our results also clarify how the composability of physical experiments is recovered, while highlighting the essential role of relativistic causality and the Fock space structure.
Steering spin fluctuations in lattice systems via two-tone Floquet engineering
Authors: Peña Ruben , Torres Felipe , Romero Guillermo 
Published: December 2024

Abstract
We report on the control of spin pair fluctuations using two-tone Floquet engineering. We consider a one-dimensional spin-1/2 lattice with periodically modulated spin exchanges using parametric resonances. The stroboscopic dynamics generated from distributed spin exchange modulations lead to spin pair fluctuations reaching quasi-maximally correlated states and a subharmonic response in local observables, breaking the discrete-time translational symmetry. We present a protocol to control the interacting many-body dynamics, producing spatial and temporal localization of correlated spin pairs via dynamically breaking correlated spin pairs from the edges towards the center of the lattice. Our result reveals how spin fluctuations distribute in a heterogeneous lattice depending on parametric resonances. This may open new routes for exploring distinct nonequilibrium states of matter and the conduction of quasiparticles in quantum materials.
Wakefield generation via propagation of two-color asymmetric laser pulses in plasma
Authors: Singh Saumya , Mishra Dinkar , Verma Nirmal Kumar , Kumar Bhupesh , Jha Pallavi 
Published: December 2024

Abstract
This paper deals with the evolution of longitudinal wakefields generated behind two-color asymmetric laser pulses through homogeneous plasma, using numerical model. The two laser pulses are linearly polarized and are assumed to have frequency difference equal to the plasma frequency. Laser pulses are either positively skewed or negatively skewed with respective asymmetric parameters. Combinations of asymmetric parameters are varied for two laser pulses to optimize the amplitude of wakefield. Maximum enhancement of wake amplitude is reported when both asymmetric laser pulses are positively skewed. Further, particle-in-cell simulations have been performed using Vsim code. The simulation study validates the results obtained via numerical model.
Parity symmetry breaking of spin-j coherent state superpositions in Gaussian noise channel
Authors: El Alaoui B , Slaoui A , Lakhfif A , Ahl Laamara R 
Published: December 2024

Abstract
The Wigner function and Wigner-Yanase skew information are connected through quantum coherence. States with high skew information often exhibit more pronounced negative regions in their Wigner functions, indicative of quantum interference and non-classical behavior. Thus, the relationship between these two concepts is that states with high quantum coherence tend to display more non-classical features in their Wigner functions. By exploiting this relationship, which manifests as parity symmetry and asymmetry, we analyze parity symmetry and asymmetry in the superposition of two spin coherent states for a spin-1/2, as well as for a general spin-j. This analysis shows that the preservation of the parity asymmetry, or the violation of the parity symmetry, correlates with an increase in the value of spin j. Additionally, we investigate the behavior of parity symmetry and asymmetry of these states subjected to a Gaussian noise channel. Specifically, we examine how this parity symmetry and asymmetry change and identify the points at which parity symmetry is violated in the spin-1/2 cat state. Notably, the violation of parity symmetry becomes more pronounced at higher values of the decoherence parameter s. Our study shows how the spin value j affects the breaking of parity symmetry in general spin-j cat states that are hit by Gaussian noise.
A parallel and improved goal-oriented adaptive finite-element approach for 3-D direct current resistivity anisotropic forward
Authors: Qiu Lewen , Tang Jingtian , Liu Zhengguang 
Published: December 2024

Abstract
This study presents a parallel and accurate adaptive finite element algorithm for 3-D anisotropic direct current (DC) resistivity forward modeling. It enables the simulation of 3-D complex environments, including undulating topography, intricate subsurface structures, and arbitrary anisotropic distributions. The study improves the goal-oriented posterior error estimation strategy by introducing a volume factor into the dual problem. This improvement not only enhances the numerical accuracy of measurement points located far from the source but also improves the error distribution within the measurement region. Additionally, to solve the linear equation system, we employ an algebraic multigrid preconditioned conjugate gradient solver. Furthermore, to accelerate the solving of large-scale 3-D problems, the domain decomposition technique is incorporated into the solver. The newly developed algorithm’s high accuracy is validated through a two-layer anisotropic model. Compared with published results, the testing results on a 3-D synthetic model with undulating topography demonstrate the algorithm’s efficiency in terms of solving time and memory usage.
Application of microgravity measurements in urban underground space exploration
Authors: Zongyu Zhang , Peng Yuan , Jiajun Zhang , Linling Li , Xinyi Huang , Zhenghao Shen , Zhongkun Qiao 
Published: December 2024

Abstract
Urban underground space exploration is an important way to solve urban underground problems, Identifying the geological structure of urban underground space is of great significance for urban development. Gravity exploration is one of the most commonly used and effective geophysical exploration methods, using a high-precision gravimeter to collect small changes in the gravity field within the survey area and obtain underground spatial anomalies through data analysis. This paper introduces the gravity exploration method, elaborates on the principle of microgravity measurement, constructs a cavity anomaly model, and conducts simulations to provide theoretical support for carrying out gravity measurement. Finally, experimental tests of the cavity model were carried out at the test site to verify the feasibility of microgravity measurement in urban underground space detection.
Study on MT data processing and denoising in southern Hunan
Authors: Yin Zihui , Guo Rongwen 
Published: December 2024

Abstract
The magnetotelluric method is a geophysical method that uses natural electromagnetic field sources to explore deep geoelectric structures. However, with the development of the economy and the generalization of human interference, the signals collected in the field are susceptible to various noise interferences. This article intends to use the current Some denoising methods process the actual collected interfered signals to obtain robust impedance estimation results.
Self-potential signal processing based on NMF
Authors: Zou JinFeng , Cui Yi-an , Xie Jing 
Published: December 2024

Abstract
In recent years, new algorithms have been continuously applied in the field of geophysical data processing, all of which have achieved good results. However, there is currently no dedicated signal separation method for self-potential field signal processing. In this paper, we propose a self-potential signal separation algorithm based on non-negative matrix factorization (NMF) to perform blind source signal separation. We aim to separate different self-potential signals from the collected mixed signals, laying the foundation for subsequent work such as feature recognition. We utilized analytical formulas of simple polarization bodies and forward modeling procedures to generate a series of self-potential signal data. Subsequently, we conducted numerical simulation experiments for signal separation. The numerical simulation results demonstrate that the proposed algorithm is capable of separating self-potential signals of different models from mixed signals.