bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of atomic configuration and biaxial strain on the electronic properties of

Cd

x

Zn

1
−
x

Te

and

Hg

1
−
x

Cd

x

Te

alloys: a first principles study
Authors: Alowa F , Matsubara M , Schaake C , Bellotti E
Published: February 2025

The electronic properties of CdZnTe and HgCdTe alloys intended for ionizing radiation and infrared detection applications are studied using first-principles calculations based on density functional theory. The Heyd, Scuseria, and Ernzerhof functional and the modified Becke–Johnson potential are employed to predict the band gap and bowing parameters of the ternary alloys over the full composition range. We demonstrate the impact of the atomic disorder on the band gap energy and thermodynamic stability of the alloys by analyzing all distinct atomic arrangements of supercells up to 16 atoms. Subsequently, we investigate the impact of biaxial strain in the (001), (111) and (112) crystal planes on the electronic properties of binary ZnTe, CdTe, and HgTe compounds, as well as the ternary alloys with composition

x
=
25
%

, 50% and 75%. We observe distinct behavior of the compounds under tetragonal and trigonal deformations, particularly for the semimetal HgTe and its alloys, where we find an unexpected non-linear band gap dependence of HgCdTe on the Cd composition, strain orientation, and strain magnitude. These results can be used to aid in the design of optoelectronic devices with targeted functionality.
An IoT-based quality inspection robot for measuring conductor sag and detecting defects in ultra-high voltage overhead transmission lines
Authors: Song Jiayin , Jiang Zhuoyuan , Zhou Jiancai , Zhu Qinglin , Liao Ting , Lu Teng , Wang Jinlong , Zhou Hongwei , Yang Liusong , Song Wenlong
Published: February 2025

Aiming to solve the urgent problem of sag measurement in constructing ultra-high voltage (UHV) power transmission lines non-line-of-sight conditions, we have developed an internet of things-based quality inspection robot for UHV overhead transmission line conductors to assist in construction. This robot not only improves the accuracy of sag measurement but also possesses the function of detecting and locating line defects. Utilizing sensors, it monitors sag, environment, and operating conditions in real-time and uploads the results to a cloud platform. The proposed lightweight YOLOv5s-SGSW algorithm, deployed on NVIDIA Jetson TX2, detects transmission line defects with 81.9% precision at 35.62 FPS. The integration of autonomous positioning algorithms and defect detection locates the defects on the transmission line. The relative errors are 0.25% for the X-coordinate and 2.07% for the Y-coordinate of the defect localization. A new tension-based sag compensation method is proposed to compensate for the sag error caused by the robot’s weight, with experimental results showing an error of 1.3%. This indicates that the robot can meet the expected design goals and satisfy the practical engineering requirements.
Sequence equicontinuity, bounded sequence complexity and rigidity
Authors: Li Jie , Li Zhijin , Zhao Jianjie
Published: February 2025

In this paper, in both topological and measure-theoretical senses, various types of sequence equicontinuity and bounded sequence complexity via Furstenberg family are introduced, and the interrelationships among which and rigidity are systematically studied, which generalize many known results in the literature. In particular, it is shown that a topological dynamical system (X, T) is uniformly rigid iff it is

F

r

-equicontinuous of type 4 iff it has bounded

F

r

-complexity of type 4; And a measure-preserving system

(
X
,

B

X

,
μ
,
T
)

is rigid iff it is µ-

F

r

-mean equicontinuous of type 4 iff it has bounded µ-

F

r

-mean complexity of type 4, where

F

r

is the Furstenberg family consisting of all sequences like

q

N

(

q
∈

N

). Moreover, several examples are also constructed to distinguish the new notions or illustrate the scopes of some conclusions, while concurrently addressing a few questions posed in earlier articles.
Characterizing the magnetic noise power spectrum of dark spins in diamond
Authors: Williams Ethan Que , Ramanathan Chandrasekhar
Published: February 2025

The coherence times of solid-state spin qubits are often limited by the presence of a spin bath. Characterizing the spectrum of the local magnetic field fluctuations of the bath is key to understanding spin qubit decoherence. Here we use pulsed electron paramagnetic resonance (pEPR) based noise spectroscopy to measure the magnetic noise power spectra for ensembles of P1 (substitutional nitrogen) centers in diamond that typically form the bath for NV (nitrogen-vacancy) centers. The Carr-Purcell-Meiboom-Gill (CPMG) dynamical decoupling experiments on the P1 centers were performed on a low [N] CVD (chemical vapor deposition) sample and a high [N] HPHT (high-temperature, high-pressure) sample at 89 mT. We characterize the NV centers of the latter sample using the same 2.5 GHz pEPR spectrometer. All power spectra show two distinct features, a broad component that is observed to scale as approximately 1/ω^{0.7-1.0}, and a prominent peak at the 13C Larmor frequency. The behavior of the broad component is consistent with an inhomogeneous distribution of Lorentzian spectra due to clustering of P1 centers, which has recently been shown to be prevalent in HPHT diamond. We develop techniques utilizing harmonics of the CPMG filter function to improve characterization of high-frequency signals, which we demonstrate on the 13C nuclear Larmor frequency. At 190 mT this is 2.04 MHz, 5.7 times higher than the CPMG modulation frequency (<357 kHz, hardware-limited). Understanding the properties of the bath allow us to either exploit it as a quantum resource or optimize decoupling performance, while also informing sample fabrication technologies. The techniques are applicable to ac magnetometry for nanoscale nuclear magnetic resonance and chemical sensing.
Kramers–Henneberger atoms in flattened Gaussian beams
Authors: Leung Ioksang , Zhu Mingyu , Wang Pingxiao , Wei Qi
Published: February 2025

The dichotomy structure is one of the prominent features of Kramers–Henneberger (KH) atoms. Within a focused laser field, the wave function of KH atoms becomes polarized due to ponderomotive (PM) forces induced by light intensity gradients, leading to the disruption of the dichotomy structure. In a Gaussian-focused laser field, the PM forces are negligible only along the optical axis. To maintain the dichotomy structure of KH atoms over a broader area, we compared the result of flattened Gaussian laser beams with Gaussian-focused laser beams. By calculating the wave functions of ground KH state hydrogen atoms at various radial and angular locations in the laser focusing plane, it was demonstrated that under suitable laser parameters, the dichotomy structure can be fully or partially preserved in flattened Gaussian laser beams. Through the dichotomy structure of KH atoms, we can verify the existence of KH atoms using interference fringes of multi-photon ionization signals.
Statistical analysis of Revan topological indices for drug compounds used in treatment of tuberculosis
Authors: Shenoy B Gautham , M Vishu Kumar , Acharya Divya , H M Nagesh , Poojary Prasanna
Published: February 2025

One of the most infectious diseases, tuberculosis (TB) has a higher death rate than HIV/AIDS, and as a result of the COVID-19 pandemic, there is concern that the number of TB cases may increase. With the aid of QSPR models, the pharmaceutical industry is continuously searching for methods to enhance medication design procedures to stop the spread of infections and treat recently discovered syndromes or genetically based dysfunctions. QSPR models are mathematical tools that utilize structural properties to establish relationships between a molecular structure and its physicochemical attributes. One way to generate attributes from the molecular graph without the need for experimental measurements is to use topological indices. The goal of this work is to create a QSPR model for tuberculosis drugs and their many physicochemical characteristics using degree-based topological indices.
Design of wide bandwidth metamaterial for biosensor and wireless application
Authors: Ankit  , Kishor Kamal , Sinha Ravindra Kumar
Published: February 2025

We present a new design and study of metamaterial (MTM) structure for wide bandwidth for biosensor and wireless applications. The geometrical parameters were analyzed and optimized for a triple-band operation in the frequency range of 0.1–16 GHz. The propagation characteristics were obtained using Finite element method. The proposed MTM provides negative permittivity at 1.4 GHz and negative permeability in the 9–16 GHz region. The proposed design exhibits left-handed characteristics in L, C, and Ku microwave region’s frequency band. The electric field (E), magnetic field (H), and surface current distribution of the proposed MTM unit cell have been studied at three different resonance frequencies. The proposed MTM design has a wide bandwidth of 2.2 GHz in C-band and a high effective medium ratio (EMR) of 13.37. The performance of the sensor is evaluated for different biomedical samples in the refractive index range of 1.00 to 1.39. The results indicate that the proposed biosensor has a high sensitivity in triple band of microwave region. The present research work can be highly suitable for Wi-Fi and satellite applications due to its overall performance, including wide bandwidth in the C-band, high EMR, and triple band operation.
Optimized hydrothermal transformation of WO3 nanorods into WS2 based catalysts: enhanced hydrogen evolution performance and synergistic effects with CNT
Authors: Ghanghass Anjali , Bhatia Ravi
Published: February 2025

Tungsten disulfide (WS2) has emerged as a cost-effective electrocatalyst for hydrogen generation. This study systematically evaluates the electrocatalytic hydrogen evolution reaction (HER) activity of WS2 nanoflakes synthesized under varying hydrothermal conditions. Furthermore, WS2/carbon nanotubes (CNT) hybrid structures were synthesized via a facile hydrothermal synthesis approach. The incorporation of CNT into the WS2 matrix significantly enhances charge transfer by providing a conductive pathway, thereby improving HER kinetics. The reduced charge transfer resistance observed in the WS2/CNT hybrid structure facilitates charge transfer at electrode/electrolyte interface, accelerating the HER process. These findings underscore the potential of WS2/CNT hybrid structures as efficient and cost-effective electrocatalysts for advancing hydrogen generation technologies.
Impact of cation distribution in shaping the structural and magnetic characteristics of Ni-Cu ferrite
Authors: Mazurenko J , A K Sijo , Kaykan L , Michalik J M , Gondek Ł , Szostak E , Zywczak A
Published: February 2025

This study presents the synthesis, characterization and magnetic properties of of Cu1−XNiXFe2O4 nanocrystalline ferrites (0.0 ≤ × ≤ 1.0) using the sol–gel autocombustion method at a neutral pH. The samples were characterized by x-ray powder diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), vibrating sample magnetometry (VSM) and Mossbauer spectroscopy. The structural analysis confirmed the formation of mixed spinel structures, with crystallite sizes ranging from 22–32 nm. Mössbauer spectra of 57Fe were recorded at room temperature (300 K) and liquid nitrogen temperature (77 K), and variations in line width, isomer shift, quadrupole splitting, and hyperfine magnetic field magnitudes were calculated for both tetrahedral and octahedral sublattices. The cation distribution, revealed through XRD, VSM and Mössbauer spectroscopy, shows a consistent pattern with nickel ions predominantly occupying octahedral sites. The magnetic properties were modified by substituting nickel ions with copper ions, affecting the distribution of magnetic Fe3+ ions and the total magnetization. The maximum saturation magnetization and coercivity reached 59.54 emu g−1 and 327.8 Oe, respectively. These findings reveal a systematic modification of magnetic properties through nickel substitution, resulting in enhanced saturation magnetization and coercive force. Notably, the synthesized samples exhibit sufficiently high magnetic properties, making them suitable for practical applications such as magnetic hyperthermia, a promising therapeutic approach for cancer treatment. The nanoparticles can be designed to generate heat in response to an alternating magnetic field, allowing for targeted and controlled heating of tumor cells.
Effect of fine-tuned growth temperature on structural, morphological, and electrical properties of Cu2O nanoparticles as candidates for supercapacitor applications
Authors: Hashim Hisham , Abdelfatah Mahmoud , El-Shaer Abdelhamid , Abdelwahed Abeer R
Published: February 2025

Cuprous oxide (Cu2O) nanoparticles are promising candidates for optoelectronic and energy applications owing to their unique p-type semiconducting properties. This study investigates the effects of precisely controlled synthesis temperatures (45°, 55°, 65°, and 75 °C) on the structural, morphological, and electrical characteristics of Cu2O nanoparticles synthesized through a coprecipitation method. X-ray diffraction (XRD) analysis confirms high crystallinity with an average crystallite size of approximately 29 nm, while transmission electron microscopy (TEM) reveals an average particle size of about 50 nm. Scanning electron microscopy (SEM) demonstrates a morphological evolution from spherical to cubic structures with increasing aging temperature. The electrical properties were investigated through AC conductivity and dielectric measurements over a temperature range of 300 K to 550 K and frequencies from 100 Hz to 5 MHz. The results show that Cu2O nanoparticles enhance supercapacitor performance through their high dielectric constant at low frequencies, improved energy storage capabilities, and increased AC conductivity for efficient charge transport. Their temperature-dependent behavior and ability to minimize energy losses make them ideal candidates for high-frequency and high-temperature applications. This work demonstrates the exceptional dielectric properties of Cu2O nanoparticles and their significant sensitivity to subtle changes in growth temperature, enabling the optimization of their characteristics for supercapacitor energy applications and emerging optoelectronic devices.
High-efficiency lead-free perovskite solar cells with MXene and NiO as transport layers: a numerical study
Authors: Shaw Nabin Kumar , Maharana Basudeba , Chatterjee Shyamal
Published: February 2025

Perovskite solar cells (PSC) are attracting a lot of interest in the scientific communities. It is one of the most promising candidates for solar cells, providing a maximum efficiency of about 30% in recent years. These PSCs could be fine-tuned to enhance their performance using various transport layers. This work demonstrates the design and analyses of the lead-free, MXene-based solar cell model with the flexible architecture of FTO/Mo2TiC2/CH3NH3SnI3/NiO. The attention has been focused on the novel two-dimensional materials called MXenes (Mo2TiC2 in present study) as electron transport layer (ETL) and NiO as hole transport layer (HTL). We have demonstrated the effect of transport layers on the overall performance of the device by varying parameters such as thickness, electron affinity, defect density of the absorber, and doping concentrations. The simulations were conducted using the Solar Cell Capacitance Simulator (SCAPS-1D) software to evaluate the performance of the solar cell. Comparisons with different HTL and back metal contacts are also studied for better understanding of the performance. The simulated model shows that the presented device structure has a potential to achieve a maximum efficiency of about 31%. This simulation is expected to provide valuable insight to the solar cell research community to explore MXene based solar cells to investigate further to maximize the efficiency and achieve the practical device.
Enhancing system stability: robust control strategies for modular multilevel converters in weak grid and load conditions
Authors: Lavanya Komma , Karlapudy Alice Mary , Garimella Saraswathi
Published: February 2025

This paper focuses on operating a modular multilevel converter (MMC) under diverse operating conditions, particularly during weak grid scenarios. The system may approach instability as a result of changes in the resonance frequency and, subsequently, the grid impedance. To address the significant impedance variations between the converter and grid as outlined in IEEE standards 519 and DIN EN 61000-4-15, this paper proposes a novel hybrid damping approach to manage the converter under such conditions. This approach is used to reduce the extra power loss from passive damping and simultaneously increase the robustness of active damping. Various passive damping and hybrid damping methods are implemented to the proposed MMC model and their comparative analysis is presented in order to identify the stability attributes. Also, this paper provides a straightforward proportional resonant (PR) controller along with biquad filter-based approach that ensures system stability and improves system robustness. A detailed sensitivity evaluation of the cascaded control loops is conducted, with an emphasis on the effect of filter parameter variations on stability. Furthermore, the paper explores the contemporary circulating current references for MMCs. This approach offers a superior alternative approach to inject specific harmonics into circulating currents. Employing these schemes, this paper demonstrates the successful achievement of low voltage ripples. Simulation and experimental data are used to validate the proposed strategies’ enhanced stability.
High-Throughput Discovery of Kagome Materials in Transition Metal Oxide Monolayers
Authors: Wang Renhong , Wang Cong , Li Ruixuan , Guo Deping , Dai Jiaqi , Zong Canbo , Zhang Weihan , Ji Wei
Published: February 2025

Kagome materials are known for hosting exotic quantum states, including quantum spin liquids, charge density waves, and unconventional superconductivity. The search for kagome monolayers is driven by their ability to exhibit neat and well-defined kagome bands near the Fermi level, which are more easily realized in the absence of interlayer interactions. However, this absence also destabilizes the monolayer forms of many bulk kagome materials, posing significant challenges to their discovery. In this work, we propose a strategy to address this challenge by utilizing oxygen vacancies in transition metal oxides within a "1+3" design framework. Through high-throughput computational screening of 349 candidate materials, we identified 12 thermodynamically stable kagome monolayers with diverse electronic and magnetic properties. These materials were classified into three categories based on their lattice geometry, symmetry, band gaps, and magnetic configurations. Detailed analysis of three representative monolayers revealed kagome band features near their Fermi levels, with orbital contributions varying between oxygen 2p and transition metal d states. This study demonstrates the feasibility of the "1+3" strategy, offering a promising approach to uncovering low-dimensional kagome materials and advancing the exploration of their quantum phenomena.
Study and circuit design of stochastic resonance system based on memristor chaos induction
Authors: Liang Qi , Yu Wen-Xin , Xiao Qiu-Mei
Published: February 2025

Memristor chaotic research has become a hotspot in the academic world, however, there are few explorations combining memristor and stochastic resonance, and the correlation research between chaos and stochastic resonance is still in the preliminary stage. In this paper, we focus on the stochastic resonance induced by memristor chaos, which enhances the dynamics of chaotic systems through the introduction of memristor and induces the memristor stochastic resonance under certain conditions. Firstly, the memristor chaos model is constructed, and the memristor stochastic resonance model is constructed by adjusting the parameters of the memristor chaos model. Secondly, the combination of dynamics analysis and experimental verification is used to analyze the memristor stochastic resonance and to investigate the trend of the output signal of the system under different amplitudes of the input signal. Finally, the practicality and reliability of the constructed model are further verified through the design and testing of the analogue circuit, which provides a strong support for the practical application of the memristor chaos induced stochastic resonance model.
Regulation of superconductivity in Nb thin fllms induced by interstitial oxygen atoms
Authors: Liu Yuchuan , Yang Ming , Fan Yun , Xu Zulei , Wu Yu , Liu Yixin , Peng Wei , Mu Gang , Lin Zhi-Rong
Published: February 2025

The regulation of superconductivity in thin films can provide important information on low-dimensional superconducting properties, and also has important reference values for the application in superconducting devices. Herein, we report the successful regulation of both the superconductivity and normal-state properties of Nb films in a wide range by the controllable introduction of interstitial oxygen atoms. The lattice parameter is enhanced for a extent as large as 4.4%, and the normal-state resistivity ρn
is tuned for more than 15 times. The slope of upper critical fleld near Tc
shows a close correlation with ρn
in a wide range. Importantly, it is found that the suppression of Tc
by disorder reveals a linear dependence with ρn in the region with an unchanged crystalline quality, which can be understood based on the picture of three-dimensional ballistic motion.
Superconductivity in Titanium Probed by AC Magnetic Susceptibility to 120 Gpa
Authors: Song Jing , Liu Hongyu , Wang Xiancheng , Jin Changqing
Published: February 2025

We used a highly sensitive ac magnetic susceptibility technique to probe superconductivity in elemental titanium (Ti) under extreme pressures to 120 GPa in a diamond anvil cell (DAC). The measurements reveal that the critical temperature (Tc) of Ti rises monotonically with increasing pressure, reaching 6.1 K at 120 GPa. Our results confirm the bulk nature of the superconductivity in Ti, as evidenced by a robust diamagnetic response in the ac magnetic susceptibility. Our work provides a routine technique to probe Meissner effect of elemental superconductors at megabar pressures.
Non-negligible Influence of Vacancies and Interlayer Coupling on Electronic Properties of Heavy Ion Irradiated SnSe2 FETs
Authors: Gao Shifan , Ma Siyuan , Zhan Shengxia , Zhu Pengliang , Liu Jie , Xu Lijun , Zhai Pengfei , Hu Peipei , Li Yan
Published: February 2025

Influences of swift heavy ion (SHI) irradiation induced defects on electronic properties of the bulk SnSe2 based FETs are explored. Latent tracks and amounts of Se vacancies in the irradiated SnSe2 were confirmed. Red shift of the A1g peak indicates that the resonance frequency of the phonons is reduced due to the defect generation in SnSe2. The source-drain current Ids
increased at ion fluence of 1×1010 ions cm-2, which was attributed to the irradiation caused Se vacancies, which hence increases the concentration of conduction electrons. The carrier mobility was about 16.9 cm2V-1s-1 for the devices irradiated at ion fluence of 1 × 109 ions cm-2, which was benefit from heavy ion irradiation enhanced interlayer coupling. The mechanism of device performance optimization after irradiation is discussed in detail. This work provides evidence that, given the electronic properties of two-dimensional material-based device, vacancies and interlayer coupling effects caused by SHI irradiation should not be ignored.
Pressure-Driven Crystal Structure Evolution in RbB2C4 Compounds
Authors: Liu Jinyu , Liu Ailing , Wang Yujia , Gao Lili , Zhang Miao
Published: February 2025

As an extreme physical condition, high pressure serves as a potent means to substantially modify the interatomic distances and bonding patterns within condensed matter, thereby enabling the macroscopic manipulation of material properties. We employed the CALYPSO method to predict the stable structures of RbB2C4 across the pressure range from 0 to 100 GPa and investigated its physical properties through first-principles calculations. Specially, we put forward four novel structures, namely P63/mcm-, Amm2-, P1, and I4/mmm-RbB2C4. Under pressure conditions, electronic structure calculations reveal that all of them exhibit metallic characteristics. The calculation results of formation enthalpy show that the P63/mcm structure can be synthesized within the pressure range of 0-40 GPa. Specially, the Amm2, P1, and I4/mmm structures can be synthesized above 4, 6, 10 GPa, respectively. Moreover, the estimated Vicker’s hardness value of I4/mmm-RbB2C4 compounds is 47 GPa, suggesting that it is a superhard material. Interestingly, this study uncovers the continuous transformation of the crystal structure of RbB2C4 from a layered configuration to folded and tubular forms, ultimately attaining a stabilized cage-like structure under the pressure span of 0 to 100 GPa. The application of pressure offers a formidable impetus for the advancement and innovation in condensed matter physics, facilitating the exploration of novel states and functions of matter.
Well defined phase boundaries and superconductivity with high Tc in PbSe single crystal
Authors: Hu Jiawei , Meng Yanghao , Zhang He , Zhong Wei , Zhai Hang , Yu Xiaohui , Yue Binbin , Hong Fang
Published: February 2025

Lead chalcogenides represent a significant class of materials that exhibit intriguing physical phenomena, including remarkable thermoelectric properties and superconductivity. In this study, we present a comprehensive investigation on the superconductivity of PbSe single crystal under high pressure. The signature of superconducting (SC) transition starts to appear at 7.2 K at 16.5 GPa. Upon further compression, the SC temperature (Tc
) decreases, and it is reduced to 3.5 K at 45.0 GPa. The negative pressure dependent behavior of Tc
is consistent with the trend of Tc
- P relations observed in other lead chalcogenides. The highest Tc
is 8.0 K observed at 20.5 GPa during decompression process, which is also the highest record among all other PbSe derivatives, such as doped samples, superlattices, and so on. The phase boundaries of the structural and electronic transitions are well defined by Raman spectroscopy, and then phase diagrams are plotted for both compression and decompression processes. This work corrects the previous claim of positive pressure dependence of Tc
in PbSe and provides clear phase diagrams for intrinsic superconductivity in PbSe under pressure.
Electron Momentum Spectroscopy Study on Trifluorobromomethane: Electronic Structure and Electron Correlation
Authors: Chen Guangqing , Niu Shanshan , Tang Yanguo , Zhang Yuting , Liu Zhaohui , Xu Chunkai , Wang Enliang , Shan Xu , Chen Xiangjun
Published: February 2025

We present a comprehensive electron momentum spectroscopy study on the electronic structure of trifluorobromomethane. The binding energy spectrum and electron momentum profiles of the entire outer-valence orbitals and the first inner-valence orbital along with several shake-up states were measured by using a high-sensitivity (e, 2e) apparatus at an electron impact energy of 1213 eV. Theoretical calculations employing the density functional theory with B3LYP hybrid functional and the symmetry-adapted cluster configuration-interaction method were performed to interpret the experimental results. Important effects of electron correlations in the initial neutral and final ionic states on the electron momentum profiles have been observed.
Effect of modulated heat source on diffusive and avalanche-like transport
Authors: Cho Y.W. , Garbet X. , Varennes R. , Qu Z.S. , Donnel P. , Obrejan K. , Grandgirard V.
Published: February 2025

We utilize the global full-F gyrokinetic code GYSELA to analyze the nonlocal transport in the presence of modulated heat source, the period of which is in the range of a transport timescale. In submarginal stable case, it is observed that a localized and time-modulated heat source can trigger both diffusive and avalanche-like transport. When heat source-stimulated nonlocal transport occurs, propagation of turbulence is faster than that of heat pulse. In addition, the propagation speed is correlated with both turbulence intensity and period of modulated source. This correlation is also identified from the analytic expression derived from two-field critical gradient model.
Hybrid simulation study on ion heating by low-frequency wave excited in a field-reversed configuration
Authors: Urano Takahiro , Takahashi Toshiki , Mizuguchi Naoki , Asai Tomohiko , Okada Shigefumi
Published: February 2025

In this paper, we use hybrid simulation to elucidate the plasma heating mechanism due to waves excited in Field-Reversed Configuration (FRC) plasma. The plasma parameters are a separatrix radius of 0.16 m and a separatrix length of 1.16 m (x-point position is z = ± 0.57 m). The wave excitation antenna consists of two loop antennas with a radius of 0.3 m and is placed at a position of z = ± 0.5 m. The current waveform of the antenna is a sine wave with a maximum current value of 30 kA and a frequency of 160 kHz. The simulation results showed that the excited waves caused compression/expansion of the plasma, and at the same time, the temperature of the plasma increased or decreased at the compressed/expanded position. When waves are applied, a 23% increase in the volume-averaged ion temperature in the separatrix is observed compared to the case without waves applied. On the other hand, no increase in electron temperature is observed. For the electron fluid, the adiabatic condition is well established, and temperature changes are observed as the plasma compressed and expanded. On the other hand, for ions, kinetic energy perpendicular to the magnetic field lines increases during compression, and part of this energy is transferred to the energy of the parallel component by collisionless pitch angle scattering, resulting in heating due to the so-called magnetic pumping.
Phase-2 CMS DAQ — growing from prototype boards to demonstrator systems
Authors: Alawieh Jaafar , Durasov Miguel , Behrens Ulf , Bocci Andrea , Branson James , Brummer Philipp , Bugajski Jan , Cittolin Sergio , Mariscot Albert Corominas I. , Darlea Georgiana-Lavinia , Deldicque Christian , Dobson Marc , Dvorak Antonin , Gaile Antra , Gigi Dominique , Glege Frank , Gomez-Ceballos Guillelmo , Gorniak Patrycja , Hansen Magnus , Hegeman Jeroen , James Thomas , Jayakumar Tejeswini , Karimeh Wassef , Kostala Dimitra , Krawczyk Rafal , Li Wei , Long Kenneth , Meijers Frans , Meschi Emilio , Morović Srećko , Odetayo Babatunde , Orsini Luciano , Paus Christoph , Petrucci Andrea , Pieri Marco , Rabady Dinyar , Racz Attila , Rizopoulos Theodoros , Sakulin Hannes , Schwick Christoph , Simelevicius Dainius , Troska Jan , Tzanis Polyneikis , Velez Cristina Vazquez , Zejdl Petr
Published: February 2025

For the Phase-2 upgrade of the CMS experiment, the CMS
central DAQ group designed and developed two custom ATCA
boards. These boards provide the interfaces between the sub-detector
electronics and the central CMS systems. This paper describes our
experience with the chosen prototyping strategy, with a focus on the
design modification choices made along the way. It concludes with a
brief overview of recent firmware developments, and a look at the
transition towards the full board production.
Measurement of scattering azimuthal distribution of polarized gamma-rays in compton scattering using GAGG(Ce) scintillator
Authors: Sato Riku , Hamdan Mohammad , Shimazoe Kenji , Uenomachi Mizuki , Taira Yoshitaka
Published: February 2025

Recently, the measurement of gamma-rays polarization has increasingly become important
for applications in various fields such as astrophysics and bioimaging.
Accordingly, there is a growing need for high-performance polarimeters to meet these requirements.
In this study, we fabricated the gamma-rays polarization detector using Gd3(Ga,Al)5O12(Ce) scintillator,
which has high energy resolution, high amount of luminescence, and fast decay time.
This detector mainly consists of scatterer and absorber, each of which use pixelated GAGG array.
By using this detector, the gamma-rays polarization was measured in MeV range (6.6 MeV), and the performance as polarimeter
was assessed.
Charge collection properties of a CMOS sensor produced in a 55 nm process
Authors: Zhou Zijie , Xiao Le , Chen Kai , Lu Yunpeng , Zhou Yang , Sun Xiangming , Huang Guangming , Gao Chaosong , Xie Lirong , Dai Wenjie , Zhang Guoxiang , Zhang Ying
Published: February 2025

We present the design and preliminary test results of a MAPS sensor, MIC6_Explorer1, based on a 55 nm Quad-well CMOS Image Sensor process for high-energy physics experiment vertex detector applications.
MIC6_Explorer1 consists of three large matrices and is designed to investigate the charge collection properties of the 55 nm process with various MAPS design parameters, including pixel pitch, diode geometry, reset methods, and readout circuit structure. Preliminary test results demonstrate that the pixel array with a 24 μm × 24 μm pitch achieved a 93.5% charge collection efficiency when exposed to a 55Fe source.
Dynamic quenching of self-induced and self-sustaining avalanches in double-trenched LGADs
Authors: Lastovicka-Medin G. , Kramberger G. , Mrkic D. , Baletic V. , Backovic V. , Kroll J. , Andreasson J. , Rebarz M.
Published: February 2025

This paper revisits and revises earlier findings on self-induced and self-quenched avalanches in double trench isolated LGADs, triggered by surface generation current from trench-induced defects in the interpad region. The key aspects presented in this work are: 1) self-sustained avalanches, seeded by dark current, require a positive feedback between electron impact ionization in the gain layer and hole impact ionization at trench corners, influenced by the curvature and density of electric field lines; 2) quenching depends on the suppression of the local electric field at the gain layer and trench corners.
Enhanced osteogenic differentiation in hyaluronic acid methacrylate (HAMA) matrix: a comparative study of hPDC and hBMSC spheroids for bone tissue engineering
Authors: Sanchez Ane Albillos , Teixeira Filipa Castro , Casademunt Paula , Beeren Ivo , Moroni Lorenzo , Mota Carlos
Published: February 2025

Bone tissue engineering (BTE) seeks to overcome the limitations of traditional bone repair methods, such as autografts and allografts, which are often limited by availability, donor-site morbidity, immune rejection, and infection risks. Recent advancements have highlighted the potential of spheroids or microtissues as building blocks for BTE. This study aimed to investigate the osteogenic differentiation of spheroids formed from human periosteum-derived cells (hPDCs) and bone marrow-derived mesenchymal stromal cells (hBMSCs) in a hyaluronic acid methacrylate (HAMA) matrix, using encapsulation and extrusion bioprinting methods. Results showed significant morphological changes, high viability, and osteogenic differentiation of spheroids from hPDCs or hBMSCs in three-dimensional HAMA environments. Notably, hPDC spheroids demonstrated higher mineralization capabilities and superior hydrogel colonization than hBMSC spheroids. These findings reveal the potential of HAMA bioink containing hPDC spheroids to produce mineralized bone grafts using a bioprinting approach.
Stochastic Stokes origami: folds, cusps and skyrmionic facets in random polarisation fields
Authors: Maxwell Kerr , Dennis Mark R
Published: February 2025

We consider the jacobian of a random transverse polarisation field, from the transverse plane to the Poincar\'e sphere, as a Skyrme density partially covering the sphere. Connected domains of the plane where the jacobian has the same sign—patches—map to facets subtending some general solid angle on the Poincar\'e sphere. As a generic continuous mapping between surfaces, we interpret the polarisation pattern on the sphere in terms of fold lines (corresponding to the crease lines between neighbouring patches) and cusp points (where fold lines meet). We perform a basic statistical analysis of the properties of the patches and facets, including a brief discussion of the polarisation analogue to superoscillation in scalar speckle patterns and the percolation properties of the jacobian domains. Connections with abstract origami manifolds are briefly considered. This analysis combines previous studies of structured skyrmionic polarisation patterns with random polarisation patterns, suggesting a particle-like interpretation of random patches as polarisation skyrmionic anyons.
Additive engineering of nonlinear optical properties of all-inorganic halide perovskites
Authors: Fatemi Ali , Jamshidi-Ghaleh Kazem , Tohidi Tavakkol , Bayat Farzaneh
Published: February 2025

In this study, ligand-assisted reprecipitation was used as a cost-effective and room-temperature synthesis method to produce CsPbBr3 and CsPbBr2I all-inorganic halide perovskites. CaCl2 were doped at four different concentrations into the nanocrystals to effectively engineer their nonlinear optical properties. The nonlinear responses of the prepared samples were investigated using the Z-scan technique under irradiation with a 632.8 nm He–Ne laser. Initially, the Z-scan method was examined theoretically, followed by both open- and closed-aperture Z-scan techniques to measure the nonlinear refractive (NLR) index (n
2) and nonlinear absorption (NLA) coefficient (β), respectively. The cubic perovskite nanoparticle morphology was observed via field emission electron microscopy. The size variation due to doping was analyzed using dynamic light scattering analyses. The particle sizes increased from 35 to 250 nm for CsPbBr3 and from 30 to 330 nm for doped CsPbBr2I. The self-defocusing NLR coefficient decreased from 9.3 to 4.8 × 10−8 cm2 W−1 for CsPbBr3 and increased from 5 to 13 × 10−8 cm2 W −1 for CsPbBr2I with the addition of Ca2+ ions. The NLA coefficient increased for both nanocrystals with higher doping levels. The enhanced saturable absorbing properties of doped halide perovskites suggest their potential application in Q-switching and mode-locking lasers.
Research on the influence of abrasive particle size and lapping parameters on the surface scratches of stainless steel substrates
Authors: Xie Shaoxiong , Fang Congfu , Lin Yanfen
Published: February 2025

It is of crucial importance to minimize the surface scratches that occur during abrasive processes in order to maintain the mechanical properties of products, improve surface quality and reduce subsurface cracks. However, current research lacks an evaluation index system for assessing and controlling surface scratches on stainless steel substrates. Addressing this issue, an evaluation index for scratches based on the surface topography characteristics of the workpiece is proposed, which is utilized to assess the state of scratches on the workpiece surface. First, using image processing techniques to screen 3D scratch data on the workpiece surface addresses the challenge of extracting 3D scratch features. Second, a feature evaluation metric for assessing lapping scratches is designed based on the extracted combined features. Finally, the influences of the abrasive grain size and lapping parameters on the characterization of lapping scratch features are explored and analyzed. The results of the Analysis of Variance indicate that the effect of lapping time on the number of scratches does not achieve statistical significance. Regression analysis reveals that reducing abrasive particle size and lapping pressure significantly affect the number of scratches and the average scratch depth. Furthermore, a negative correlation is observed between the rotational speed of lapping pad and the number of scratches and the average scratch depth. Among these factors, abrasive particle size has the most prominent effect on the number of scratches and the average scratch depth. Specifically, when abrasive grains with a particle size of w10 are used for processing, the minimum number of scratches observed is 28, with an average scratch depth of 315.62 nm and the density distribution coefficient value is 0.31. Compared to the abrasive particle size w50, there is a decrease of 57.58%, 52.38% and 35.48%. The use of smaller-sized abrasive grains can significantly reduce the number of scratches and render them shallower and more concentrated in distribution. This method enables the analysis of the formation mechanism and patterns of scratches under various process parameters.
Quantifying radiotherapy beam quality: an analysis using gamma passing rates
Authors: Gao Xiang , He Yipeng , Yu Yanjuan , Chen Sijia , Gao Guanglu , Fu Lirong , Shi Liwan , Kang Zheng
Published: February 2025

Purpose. PDD and profile curves play a crucial role in analyzing the beam quality and energy stability of accelerators. The aim of this study was to assess the efficacy of GPR in machine QA and compare it with traditional methods for analyzing dose outputs. Methods. GPRs were employed to assess the quality of radiation beams by comparing 1D and 2D Profile metrics and PDD data against commissioning data. The data used were obtained from the ASCII data files derived from the water tank. GPRs were calculated for all plots with a lower percentage dose cutoff of 10%. The local GPRs and dose influence for the 2D PDD metrics and dose influence were calculated for an open field 10 × 10 cm2 photon beam at SSD = 100 cm. In both 1D and 2D GPRs analyses, criterion of 1%/1 mm was adopted, as this approach allows for the capture of more subtle variations in the data. To substantiate the viability of the study, a comparative analysis was conducted by comparing the outcomes of the gamma analysis with those derived from traditional methods, such as manual machine quality assurance checks. Results. GPRs demonstrated a superior capability for comprehensive data analysis compared to traditional methods. For the 1D curves, the passing rates (γ ≤ 1) are 96.19%, 100%, and 93.46%, respectively. With respect to the 2D dose influence, the PDD image passing rate was 99.57%, and significant dose differences were observed at the four corners of the open field, indicating areas that require further investigation. Conclusions. Compared to traditional methods, GPRs are more sensitive to subtle changes in the data, providing valuable insights into the accelerator beam status.
Health and environmental risk due to acid mine drainage generating tailings in Zimapán, Mexico
Authors: Chango-Cañola Ana P , González-Sandoval María del Refugio , Alarcón-Herrera María T , García-Villanueva Luis Antonio , Fernández-Villagómez Georgina
Published: February 2025

In the mining district of Zimapán, located in the State of Hidalgo, Mexico, high concentrations of potentially toxic elements such as arsenic (As), lead (Pb), and cadmium (Cd), and Acid Mine Drainage (AMD) have been detected in tailing’s dams. This AMD, along with the population growth in the region, has reduced the distance between mining waste sites and urban areas, increasing the risk of exposure to these contaminants for living organisms. The objective of this study was to evaluate AMD generation and the risk to human health and the ecosystem due to potential exposure to elements present in the AMD, using the Spatial Analysis and Decision Assistance (SADA) software in three mining areas of Zimapán. Soil sample analyses revealed that the total concentrations of Pb, Cd, and As exceeded the maximum limits allowed by Mexican standard NOM-141-SEMARNAT-2003 for residential and agricultural land use. Additionally, the SADA model results demonstrated a potential risk to human health and mammals and birds due to their interaction with concentrations of 12,198 mg kg−1 of As and 4,618 mg kg−1 of Pb, respectively. The SADA model played a crucial role in enabling the quantification of the potential risk to the exposed population, thereby becoming an essential tool for the environmental management of this and other mining districts.
Suppression of surface amorphization during oxygen evolution reaction in A-site deficient perovskite oxides
Authors: Petlund Henrik , Pokle Anuj , Chatzitakis Athanasios
Published: February 2025

Surface restructuring and the formation of amorphous layers during the initial stages of the oxygen evolution reaction (OER) is a common phenomenon in perovskite-based catalysts. It has also been observed that catalysts following the lattice oxygen mechanism (LOM) are prone to amorphization as the rates of lattice oxygen evolution and oxygen vacancy replenishment are not equal. This is accompanied by a significant A-site cation loss in the electrolyte, ultimately leading to the collapse of the crystalline phase and the appearance of an amorphous catalytic surface of a thickness of around 10 nm. Typically, the originally crystalline material is termed as precatalyst. In this work, we hypothesize that A-site deficient perovskite precatalysts of the family of Ba
x
Gd
y
La
z
Co2O3-δ
(BGLCxyz), which operate under LOM, will have a reduced degree or no surface amorphization under OER conditions in alkaline media. For this reason, A-site deficient BGLC587 with a 20% deficiency is synthesized to validate our main hypothesis. Furthermore, thermal reduction of the A-site deficient BGLC587 precatalyst is expected, to form embedded nanoparticles on its surface through the process of exsolution, thus inducing higher surface area and improved electrocatalytic activity, while still suppressing surface amorphization.
Mechanical and thermal properties of silane-treated carbon fiber mat/pseudo-thermoplastic poly (methyl methacrylate) sheet molding compound
Authors: Bae Seoyeon , Kim Chang Dae , Kim Eunjung , Lee Sungbi , Son Euihwan , Yu Woong-Ryeol , Ahn Cheol-Hee , Na Wonjin
Published: February 2025

Sheet molding compound (SMC) is a key material in the automotive industry, but the increasing environmental concerns call for recyclable composite materials. In this study, the authors developed a novel carbon fiber mat-based SMC material using a pseudo-thermoplastic resin and investigated its fundamental mechanical properties. The authors also explored the impact of silane treatment on the SMC. The results showed that the tensile, flexural, and Izod impact strength significantly improved by up to 30%. These findings suggest that the enhanced interfacial properties due to silane treatment can substantially improve material properties. More intralayer damage propagation and cohesive interfacial failure were suggested as key mechanisms of interfacial treatment. This research provides novel insights for developing future high-performance, recyclable SMCs and offers a practical solution to the environmental challenges in the automotive industry.