bluuebunny/crossref_metadata_2025 huggingface dataset:
Generation of High-Quality Single-Photon Sources in Cavity Optomagnonics
Authors: Hou 侯 Rui 瑞 , Zhang 张 Wei 微 , Han 韩 Xue 雪 , Wang 王 Hong-Fu 洪福 , Zhang 张 Shou 寿
Published: December 2024

We propose a scheme for generating high-quality single-photon sources utilizing the conventional photon blockade (CPB) effect in a cavity optomagnonic system with Kerr nonlinearity. The realization of the CPB effect depends on both the Kerr nonlinearity and Kerr-like nonlinearity of the optical cavity, which is converted using magneto-optical coupling. The CPB effect can be realized in a cavity optomagnonic system with weak magneto-optical coupling by modulating the strength of the Kerr nonlinearity. Notably, our scheme supports photon blockade in both the strong and weak Kerr nonlinear regimes, which broadens the range of experimental parameters. Furthermore, we explored the parameter regimes where the CPB effect could not be achieved because of the combined effects of the magneto-optical coupling and Kerr nonlinearity. We also determined the optimal driving amplitude region for generating high-quality single-photon sources. This work not only provides a novel route for realizing the CPB effect but also establishes a versatile platform for producing single-photon sources with high purity and brightness.
Junctionless negative capacitance FinFET-based dielectric modulated biosensor with strain silicon integration at different FE thickness
Authors: Gandhi Navneet , Kondekar P N
Published: December 2024

Viruses such as SARS-CoV, MERS-CoV, and SARS-CoV-2 have posed serious threats to humanity in recent decades, with the COVID-19 pandemic wreaking havoc on both health and the economy. Early detection of these viruses is crucial for mitigating their effect on the immune system. In this study, we propose a dielectric-modulated biosensor realized using junctionless negative capacitance (NC) FinFET with strained silicon (StrS) integration for label-free electrical detection of neutral and charged biomolecules. The biosensor design integrates StrS within the source/drain (S/D) extension region, characterized by a Gaussian doping profile. The device employs a uniaxial stress of 1.4 GPa applied along the channel direction, which modulates the band structure to enhance carrier mobility. Additionally, a ferroelectric (FE) layer is incorporated in the gate stack, introducing a NC effect. This configuration reduces the OFF current while increasing the ON current, thereby improving the selectivity of the sensor. A ‘T-shaped’ metal support is incorporated, featuring cavities on both sides for the biomolecule’s accommodation. Our investigation focuses on the label-free detection of various biomolecules characterized by their equivalent dielectric constant (K), e.g. Streptavidin (K = 2.1), Biotin (K = 2.63), APTES (K = 3.57), Keratin (K = 8), etc. Discrimination between different biomolecules is achieved by analyzing variations in threshold voltage (V
TH), OFF current, and I
ON/I
OFF ratio as sensing metrics. The limit of detection (LoD) of the proposed sensor was meticulously estimated through a machine learning approach, achieving an impressive sensitivity with a calculated value of 0.47, quantified in terms of the ‘K’ of the biomolecules. A comprehensive analysis also involves the sensitivity and selectivity analysis with different FE thicknesses. Our study found that Pyridine (K = 12) biomolecules have the highest V
TH and OFF current sensitivity (189.57% and 85.51%, respectively), as well as the highest V
TH and OFF current selectivity over Streptavidin (1.3 and 0.811, respectively) at FE thickness of 1.8 nm. Furthermore, this paper explores the impact of low-frequency noise (i.e. flicker noise) on the noise power spectral density (PSD) of the proposed biosensor in the presence of different biomolecules. Our findings reveal that an increase in the gate coupling capacitance corresponds to the rise in K of biomolecules, leading to a decrease in noise PSD (

S

ID

/

I

D

2

) and a subsequent reduction in noise. Using well-calibrated TCAD models, the acquired results reveal that incorporating StrS leads to a ∼41% increase in the ON current over its baseline case.
Femtosecond laser multiple pulse-induced thermochemical copper precipitation from glyoxylic acid copper complex ink with surfactant
Authors: Ha Nam Phuong , Ohishi Tomoji , Mizoshiri Mizue
Published: December 2024

This paper presents the precipitation of copper (Cu) from a surfactant-added glyoxylic acid copper (GACu) complex ink, in femtosecond laser multiple pulse-induced thermochemical processes to achieve high-resolution Cu direct writing. The study specifically examines the impact of the surfactant, n-decanoylsarcosine sodium, (NDSS), on the nonlinear optical absorption properties of GACu complex ink. Findings reveal that the addition of NDSS did not alter the molecule binding and single-photon absorption properties of the ink. However, nonlinear optical absorptions evaluated through the open aperture z-scan method displayed differences between the NDSS-added and non-added GACu complex inks when subjected to femtosecond laser pulse irradiation. These results suggest that Cu nanoparticles were generated from the GACu complex ink via nucleation and surfactant-mediated growth, leading to the saturable absorption of the subsequent irradiated laser pulses. By employing a pulse repetition frequency of 5 MHz and a pulse number of 2 × 104, a minimum dot diameter of 1.6 ± 0.1 μm with stable reproductivity was attained with NDSS-added ink, corresponding to the laser spot diameter, without excessive precipitation due to thermal diffusion. This comprehensive understanding of the surfactant NDSS and pulse number effects on the Cu precipitation process holds potential for the direct writing of various materials. Furthermore, this insight offers a novel approach for affordable and scalable manufacturing with minimized environmental impact.
Bulk-like structural, magnetic and optical properties of (111)- and (001)-NiO thin films
Authors: Kaur S , Bhatia Smriti , Pooja  , Sharma Kshitij , Malik V K , Singh J P , Sen K
Published: December 2024

We have grown (111)- and (001)-oriented NiO thin films on (0001)-Sapphire and (001)-MgO substrates using pulsed laser deposition (PLD), respectively. DC magnetic susceptibility measurements underline that the Néel temperatures of the samples are beyond room-temperature. This is further confirmed by the presence of two-magnon Raman scattering modes in these films in ambient conditions. Moreover, relative intensity of the two magnon-mode with respect to a neighboring phonon mode in the films, at least down to 30 nm thickness, is comparable to the same for bulk NiO. UV–vis spectroscopy and spectroscopic ellipsometry determined that the bandgap of the films is 3.6 eV which is well within the range for bulk NiO. Thus, these indicate that the thin films are bulk-like. Further, photoluminescence measurements on (111)-NiO films obtained two-radiative transitions at 385 nm and 405 nm. The linewidth of the latter broadens towards low temperatures, indicating a plausible exciton-magnon coupling. Overall, these PLD-grown oxide films hold significant technological importance due to their optical transparency and their capacity to host robust magnons at room temperature.
An open domain fault diagnosis method for rotating machinery based on dynamic convolutional graph network and bi-classifier adversarial learning
Authors: Yang Guang , Su Juan , Du Songhuai , Duan Qingling
Published: December 2024

To address the challenges of distributional discrepancies and partially inconsistent class labels between source domain and target domain data in real-world engineering applications, this study proposes an open-domain adaptation method based on a Dynamic Convolutional Graph Network and bi-classifier adversarial learning (DCGNDAT). First, a dynamic convolution module is introduced to replace conventional convolution layers, enhancing the model’s ability to extract fault-related features from vibration signals. Second, a graph network is employed to encode structural information, thereby improving the model’s representation of complex data. Finally, a bi-classifier adversarial training mechanism is designed, incorporating entropy maximization and minimization strategies for the source and target domains, along with a binary cross-entropy scheme for target domain outputs, to accurately delineate the boundaries between known and unknown classes. Fault diagnosis experiments conducted on bearing and self-priming centrifugal pump datasets demonstrate that the proposed method achieves significantly higher recognition rates for unknown fault categories compared to existing algorithms, validating its superior diagnostic performance and robust open-domain adaptability.
Inorganic ligand capped quantum dot light-emitting diodes: status and perspective
Authors: Zhang Tianxu , Yang Xuan , Xie Bin , Luo Xiaobing
Published: December 2024

Quantum dots (QDs) have shown great application potential in a variety of optoelectronic devices due to their unique optoelectronic properties, especially playing a key role in the development of quantum dot light-emitting diodes (QLEDs). Inorganic ligands, including metal or non-metal chalcogenides, oxoanions, halides, and metal cations, play crucial roles in the synthesis, stabilization, and functionalization of QDs. Compared to long-chain organic ligands, inorganic ligands are shorter and possess higher electron mobility, which facilitates their application in high-performance QLEDs. This review explores the mechanisms of ligand exchange, classifies the types of inorganic ligands, and discusses their impact on the properties of QDs. Special attention is given to the latest research developments in inorganic ligand QDs for LEDs and their prospective applications in optoelectronics. This review highlights the versatility and efficacy of inorganic ligands, showcasing their potential to revolutionize QLED technology for future high-resolution displays and efficient optoelectronic devices.
Superior electrochemical potential of (Cd-Cu) doped PbO2 nanomaterials for energy storage applications
Authors: Danish Muhammad , Mehmood Arslan , Sandhu Zeshan Ali , Asam Raza Muhammad , Ashraf Sufyan , Ali Furqan , Bhalli Ali Haider , Aslam Muhammad , Batoo Khalid M. , Ijaz Muhammad Farzik
Published: December 2024

The improvement of effective materials for energy storage and conversion applications, predominantly for next-generation supercapacitors as electrode materials, remains a crucial task. In this research, pure lead oxide (PbO) and doped nanomaterials (Cd@PbO2 and Cu@PbO2) were prepared employing a solvothermal methodology to improve their electrochemical characteristics. Various characterization techniques, including Scanning Electron Microscopy (SEM) and X-ray Diffraction (XRD), established the crystalline structure and uniform needle-like morphology of the fabricated nanoparticles. The Tauc plot study exposed that 5% Cd-doped PbO2 (Cd@PbO2) displayed a compact band gap of 2.52 eV, demonstrating its potential for enhanced energy storage capabilities. Electrochemical performance was assessed via cyclic voltammetry (CV), cyclic stability, and electrochemical impedance spectroscopy (EIS). The 5% Cd@PbO material established a maximum specific capacitance of 789.87 F/g and energy density of 33.17 Wh/kg, then pure PbO2 and Cu@PbO2. Moreover, it maintained 90% of its initial capacitance after 3000 cycles, representing exceptional stability. The 5% Cd@PbO2 material also showed low resistance in EIS, additional supporting its suitability for energy storage applications. These outcomes acclaim 5% Cd@PbO2 as a promising candidate for supercapacitor electrode material due to its remarkable stability and performance.
Tailoring gas sensing properties of armchair graphene nanoribbons via transition metal doping: a first-principles investigation on NO, NO2, and NH3 molecules
Authors: R Jyoti , Kaur Navjot , Choudhary B C , Prior Timothy J , Sharma Ramesh K
Published: December 2024

This study explores the gas sensing capabilities of armchair graphene nanoribbons (AGNR) for nitrogen-based gases (NO, NO2, and NH3) using DFT calculations. The results show that pristine AGNR has limited sensitivity to these gases. However, doping AGNR with transition metals (Ti, V, Cr, Mn, and Fe) significantly improves its adsorption performance. The adsorption behavior is analyzed through geometrical changes, binding energies, binding distances, density of states, and band structure. Notably, Mn-AGNR showed up to 20 times greater sensitivity to NO gas. For NO2, Mn-AGNR and V-AGNR demonstrated increased adsorption energies of −3.39 eV and −3.99 eV, respectively. Additionally, Fe-AGNR proved highly effective for NH3 gas adsorption. It highlights Mn-AGNR, V-AGNR, and Fe-AGNR as particularly effective for sensing NO, NO2, and NH3 gases, respectively, and offers a comparative analysis to identify optimal doping strategies for enhanced gas sensing performance.
Cylindrical gravitational waves in Einstein-Aether theory
Authors: Chan R , da Silva M F A , Satheeshkumar V H
Published: December 2024

Along the lines of the Einstein-Rosen wave equation of General Relativity (GR), we derive a gravitational wave equation with cylindrical symmetry in the Einstein-aether (EA) theory. We show that the gravitational wave in the EA is periodic in time for both the metric functions Ψ(r, t) and H(r, t). However, in GR, Ψ(r, t) is periodic in time, but H(r, t) is semi-periodic in time, having a secular drifting in the wave frequency. The evolution of wave pulses of a given width is entirely different in both theories in the H(r, t) metric function due to this frequency drifting. Another fundamental difference between the two theories is the gravitational wave velocity. While in GR, the waves propagate with the speed of light, in EA, there is no upper limit to the wave velocity, reaching infinity if c
13 → 1 and zero if c
13 → − ∞. We also show that energy-momentum pseudotensor and superpotential get contributions from aether in addition to the usual gravitational field part. All these characteristics are observational signatures that differentiate GR and EA that might aid in the search for new physics in the cosmological background of stochastic gravitational waves discovered recently by the Pulsar Timing Array collaborations such as NANOGrav, EPTA, PPTA, InPTA, and CPTA.
Experimental verification of a tighter wave-particle duality based on quantum coherence
Authors: Yang Xiaowan , Zhao Xinzhi , Zheng Tianle , Cheng Jiong , Zhang Chengjie
Published: December 2024

Wave-particle duality is an inherent characteristic of microscopic systems, which exhibit both wave-like and particle-like behaviors depending on the experimental setup. On the other hand, quantum coherence refers to the ability of a quantum state to preserve its superposition despite interactions and thermalization effects. In this study, we experimentally investigate a tighter wave-particle duality based on quantum coherence. We construct a heralded single-photon source and use the expect values of Pauli operators to quantify the interferometric visibility and path distinguishability of photons. By employing quantum state tomography, we reconstruct the density matrix of the quantum state and assess its quantum coherence. Our results provide experimental evidence for the tighter wave-particle duality based on quantum coherence.
Effect of pressure and current density on metastable argon dynamics in low-pressure Ar-O2 plasma
Authors: Imran Muhammad , Rehman Najeeb Ur , Wali Niaz
Published: December 2024

Non-thermal plasma demonstrates a significant enhancement in efficiency when oxygen is added into the plasma mixture, particularly in processes such as thin-film oxide deposition, poly film removal, and photoresist mask ashing. This study examines the behavior of metastable argon states (1s5 and 1s3) in Ar-O2 mixture plasma, generated by a 50 Hz pulsed DC power supply under low-pressure conditions ranging from 1 mbar to 7 mbar. The densities of metastable argon states were assessed at varying conditions of current density, argon concentration, and filling gas pressure, utilizing optical emission spectroscopy (OES). The argon emission line ratio technique was employed to determine the plasma parameters. Experimental results indicate that electron density increases with current density, driven by enhanced excitation and ionization processes, while higher argon concentrations facilitate efficient ionization. The declining trend of the electron density with an increase in filling gas pressure is attributed to higher-pressure collisional processes. Metastable argon atoms exhibit heightened density with increased current density and argon percentage but decrease with elevated pressure due to loss processes. The regulation of metastable states is crucial for processes like etching, surface modification, and sterilization, providing a crucial step to the optimization and enhancing these applications.
Simultaneous photon blockade and bunching in giant atom-cavity system
Authors: Ma Kang-Jie , Liu Jie , Cai Yue , Tan Lei
Published: December 2024

We propose an innovative model predicated on giant atom-cavity system, wherein three cavity modes are interconnected via nearest-neighbor photon tunneling, and a giant atom is simultaneously coupled with two single-mode cavities on each side. This model demonstrates both photon blockade and photon bunching effects simultaneously. Specifically, when the giant atom is weakly driven, the central cavity displays unconventional photon blockade with

g

b

(
2
)

(
0
)
≈
1

0

−
5.97

, while the side cavities exhibit photon bunching effects with

g

a

(
2
)

(
0
)
=

g

c

(
2
)

(
0
)
≈
1

0

4.85

due to the quantum interference and the anharmonicity of energy eigenvalues. This model introduces a fresh perspective for investigating intricate photon behaviors in multi-cavity systems.
Numerical simulation of electromagnetically induced transparency in composite metamaterial
Authors: Wang Junqiao , Sun Jingyi , Sun Shuai , Zhang Hao , Wang Qiaoqiao , Yang Jinyuan , Mei Yewen
Published: December 2024

In high-refractive-index dielectric nanostructure, the Mie resonance become evident, and the destructive interference of the radiation fields from electric and toroidal dipole moments results in the excitation of anapole state, which has the unique optical properties of a dark state and can support the excitation of more diverse optical phenomena, such as the electromagnetically induced transparency (EIT) effect. In this study, we performed numerical simulations of a composite metamaterial consisting of Si nanocubes and gold nanorods. The Au-Si composite structure produces an electromagnetically induced transparency spectrum based on the coupling of the optical dark channel (i. e. anapole state) and bright channel (i. e. localized surface plasmon resonance). By tailoring the surface structure of the dielectric Si cube, the surface charge and current distributions can be modified, and finally, the nonradiative anapole state may be influenced and manipulated. The results show that the modified metal/dielectric metamaterial can realize an electromagnetically induced transparency effect with a transmission of up to 95% and a refractive index sensitivity of 170 nm RIU−1.
Fabrication of three-layered aluminium-copper laminated composites using friction stir additive manufacturing
Authors: Choudhury Smrity , Thirugnanasambandam Arunkumar , Payak Viresh , Medhi Tanmoy , Saha Roy Barnik
Published: December 2024

The current study employed the friction stir additive manufacturing (FSAM) method to fabricate three-layered laminated composite by utilizing 3 mm thick sheets of AA6061-T6 alloy (top and bottom layers) and pure Cu (middle layer). The feasibility of FSAM in producing high-performance Al/Cu/Al laminated composites was evaluated by analyzing the influence of tool rotational speed on the microstructure and mechanical properties. The composites were fabricated at rotational speeds of 900 rpm, 1200 rpm, and 1500 rpm; maintaining a traverse speed of 90 mm min−1 throughout the experiments. Changes in the weld morphology, macrostructure, microstructure, and intermetallic formation were noted and analyzed. The findings indicated that achieving macro defect-free joints is possible with a rotational speed of 1200 rpm. Detailed examinations via electron dispersive spectrum and x-ray diffraction revealed the presence of AlCu, Al2Cu and Al2Cu3 intermetallic compounds within the nugget zone. Significantly varied microhardness levels ranging from 59.4 to 143.7 HV0.1 were observed, corresponding to distinct microstructural features within the processed zone. The Al/Cu laminated composite exhibited an excellent combination of strength and ductility; a UTS of 214.6 MPa and an elongation of 23.4%. The findings showcase that utilizing FSAM presents an exceptional opportunity to fabricate novel Al/Cu multilayered composites with distinctive mechanical properties.
Shear viscosity of electrorheological complex plasmas
Authors: Shakoori Muhammad Asif , Rahim Iqra , Khan Misbah , Li Haipeng , Shahzad Aamir , He Maognag
Published: December 2024

In this paper, we investigate the behavior of shear viscosity for three-dimensional electrorheological complex plasmas (CPs) liquids by using the computational method (molecular dynamics simulations) under an external AC electric field (M

T
). The Green–Kubo formula is used to calculate the shear stress autocorrelation function (A

η
(t)) and their integrals (coefficients, η) under the influence of M

T
, across numerous values of CPs parameters. By comparing the presented simulation results obtained under the absence of M

T
(=0.0) and at equilibrium strength (M

T
 = 0.007), we analyze and discuss their implications in relation to existing theoretical, simulation, and experimental findings. Our observations demonstrate that the M

T
significantly influences the shear viscosity (dynamics) of CPs. Simulation results demonstrated that decay, magnitude, and time of A

η
(t) gradually decreased with increasing the M

T
, and coefficients η increased in the order of magnitude as expected. These results identified three distinct regimes: a slight decrease in η at low M

T
intensities, high increase at intermediate, and a relatively constant behavior at higher M

T
intensities. We demonstrate that employing the Green–Kubo relation for effective interparticle potential in CPs yields safe, reliable, and accurate estimations of M

T
effects on shear viscosity. Our findings of η demonstrate the electrorheological characteristics of CPs, offering insights into phase transitions using electric fields.
Construction of exact solutions for a higher-order stochastic modified Gerdjikov–Ivanov model using the IMETF method
Authors: Khalifa Abeer , Ahmed Hamdy , Ahmed Karim K.
Published: December 2024

The multiplicative white noise in the Ito interpretation is included for the first time in the perturbed higher-order modified Gerdjikov–Ivanov (HMGI) equation, that is considered the focus of the current study. In this work, we investigate the suggested model using the improved modified extended tanh-function (IMETF) method with the goal of producing brilliant and unique solitons such as dark and bright solitons, singular and singular periodic solutions, hyperbolic wave solutions, Weierstrass elliptic doubly periodic solutions, rational, exponential function solutions and Jacobi elliptic functions (JEFs). These extracted solutions demonstrate the effectiveness and potency of the used methodology. The used method specifies our research objective, which is related to solitons. These obtained soliton solutions are useful resources for examining a range of phenomena when there is white noise present. We examine how various wave phenomena are affected by noise, with a special emphasis on soliton solutions. Our findings indicate that the phase component for the obtained solitons of the suggested governing model is the primary goal of the white noise. This study is the first to show the optical soliton solutions derived from the perturbed HMGI equation under multiplicative white noise influence. The contribution of our work is the application of this phenomenon to a model equation in a new context that neither has been studied nor discovered before for optical soliton solutions. With the derived findings, our knowledge of wave events in nonlinear optical systems has advanced significantly.
LRS Bianchi-I Universe Model with Domain Wall in f(R,T) Gravity
Authors: Çağlar Halife
Published: December 2024

In this work, strange quark matter (SQM) and normal matter (NM) attached to domain wall (DW) matter distributions have been examined for locally rotationally symmetric (LRS) Bianchi-I space-time has been investigated. The model has been constructed in the framework of f(R,T) theory for f(R,T) = R + 2μT which is suggested as an alternative gravitation theory instead of Einstein’s General Relativity Theory. Obtained modified field equations have been solved by using scale factors equation A = Bm come from the proportion of expansion scalar θ to shear scalar ϖ2. SQM and NM are added to DW with the help of equations of state (EoS) pm = 1/3 (ρm − 4Bc) and pm = (γ − 1)ρm. Pressure and energy densities of all matter distributions have been obtained depending oncosmic time t and their effects decrease by the time. It is found that DW matter behaves like stiff matter due to attaining DW pressure equal to DW energy density pDW = ρDW. Also obtained values of scale factors and some kinematic quantities give an expanding universe for the model. Energy conditions and kinematic quantities of the model have been examined in the last section. In addition, General Relativity solutions of the model have been attained by assuming μ=0 in f(R,T) = R + 2μT. All solutions have been concluded in detail.
On the evolution of ion cyclotron waves in magnetized pair ion-electron plasmas
Authors: PRAMANIK SOURAV
Published: December 2024

The evolution of low frequency, electrostatic ion cyclotron waves (ICWs) in response to weak perturbation is analytically studied in a magnetized pair ion plasma with isothermal electrons distributed according to the Maxwell-Boltzmann law. Excited ICWs travel perpendicular (nearly) to the direction of the applied magnetic field. To deal with the intrinsic nonlinearity and pair-ion dynamics, a simple perturbation technique is used to solve the governing fluid and Maxwell's equations. The stationary wave solutions show that excited ICWs slowly lose coherence nature due to the mixing of phases of adjacent particles. Wave frequency becomes space-dependent under the influence of nonlinear ponderomotive force which is self-consistently generated as the mode evolves in time. Relevant mode breaks in due course failing to maintain coherency. An approximate time is obtained when the mixing of the phases starts. The effects of the concerned parameters are discussed. Phase-mixing also mediates irreversible wave-particle energy transfer causing collisionless damping of ICWs. Obtained results can be useful in understanding the behavior of nonlinear ICWs in laboratory produced pair plasmas.
Different post-heat treatment responses on microstructure and mechanical characteristics of maraging steel 1.2709 samples produced by LPBF
Authors: V Raghuraman , Kumar T Sampath
Published: December 2024

The study focuses on the enhancement of microstructural and microhardness characteristics of Laser-Based Powder Bed Fusion (LPBF) maraging steel 1.2709 with the effect of different heat treatment (HT) conditions including aging (AT), double aging (DAT), and solutioning (ST) and compared with the as-built (AB) condition. The samples were fabricated with the LPBF process parameters, utilizing 120 W of laser power, 500 mm s−1 of scanning speed, maintaining 20 μm layer thicknesses, with the laser spot width and hatch spacing of 0.0550 mm and 100 μm respectively in the argon environment with the 45° rotating raster scanning pattern. Further the as-built and heat treated samples were evaluated utilizing electron backscatter diffraction (EBSD), Field Emission Scanning Electron Microscope (FESEM), microhardness, x-ray diffraction (XRD) and relative density. The FESEM analysis indicated that the DAT samples exhibit a more refined and uniform interdendritic grain growth of precipitates Ni3 (Al, Ti) compared to the as-built sample, which exhibited porosity and lack of fusion. Aging reduces the presence of interlayer defects, while the solution-heat-treated sample reveals the formation of lath martensite. The microhardness exhibited an increase following three distinct heat treatment conditions: AB, AT, DAT, and ST, measuring 450 HV, 650 HV, 760 HV, and 520 HV, respectively. The ferrite content was recorded at 99.6%, 87.4%, 99%, and 99.4%, while the austenite content was 0.4%, 12.6%, 1%, and 0.6%. The grain size in the ferrite phase was 8.72 μm, 6.087 μm, 6.86 μm, and 0.32 μm, and in the austenite phase the grain size was 0.26 μm, 0.86 μm, 2.51 μm, and 6.89 μm.
The magneto-electronic, structural, thermodynamic, mechanical and optoelectronic attributes of lead-free A2LiMoCl6 (A=Na, K) double perovskites: A spin-polarized DFT study
Authors: Mursaleen Inamul , Munir Junaid , Ain Quratul , Aldwayyan Abdullah S , Ghaithan Hamid , Ahmed Abdullah Ahmed Ali , Qaid Saif M H
Published: December 2024

Double perovskite halides are considered a developing class of materials in comparison to perovskite materials as they offers higher stability, tunable bandgaps and are considered great substitute for lead based perovskite materials. Magnetic double perovskites are gaining significant attention due to the creation of efficient spintronic devices. This manuscript reports the first principles analysis on lead free A2LiMoCl6 (A=Na, K) by using the FP-LAPW approach which is incorporated in the Wien2K code. For the treatment of the exchange correlation effects the mBJ approximation is employed. Structural composition and stability of A2LiMoCl6 (A=Na, K) is assessed via VESTA software and the volume optimization curves. The formation energy is computed to assess material’s thermodynamically formation. The mechanical stability of both halide based materials is evaluated through the Born’s stability. The total magnetic moment for A2LiMoCl6 (A=Na, K) is computed as 3μB. The electronic properties for both halides reveal direct bandgaps in both spin channels. Strong absorption of the UV radiations is revealed through the optical properties of A2LiMoCl6 (A=Na, K).
Tribological behaviour of injection moulded composite fabricated using bio-fiber (flax fiber), bio-filler (halloysite nanotube), and biopolymer (polylactic acid)
Authors: Debnath Mitali , Chakraborti Prasun
Published: December 2024

This study investigates the wear and frictional behavior of the flax fiber (FF)/polylactic acid (PLA)-based green composite filled with bio-filler, namely, the halloysite nanotube (HNT). The HNT/FF-PLA composite was fabricated using injection molding, considering the fixed injection pressure (90 bars), speed (60 mm sec−1), and temperature (165 °C). The HNT/FF-PLA composite was engineered with an FF length of 5 mm and 20% fiber loading. This study examined the wear and frictional behavior of engineered HNT/FF-PLA composite by exploring the intrinsic influences of tribo parameters such as the sliding speed (1 to 3 m s−1) and the applied load (10 to 30 N). The HNT/FF-PLA composite was developed by varying the HNT filler as 1, 1.5, and 3 wt%. The wear responses, such as the coefficient of friction (COF) and specific wear rate (SWR) were considered as the performance parameters to be optimized through response surface methodology (RSM). The morphology of the HNT/FF-PLA composite worn test specimens was examined by scanning electron microscope (SEM). The primary purpose of this study is to optimize the wear and frictional behavior of the engineered HNT/FF-PLA composite, advancing its application as a sustainable material with superior tribological performance. The results highlight the influence of HNT filler, sliding speed, and load on the COF and SWR, where optimal parameters were identified using the RSM. All the process parameters were found to be significant for both COF and SWR. The minimum COF was found at a sliding speed of 1.007 mm s−1., load of 25.32 N, and filler wt% of 1.007. For SWR, the optimal parametric combination is 2.986 m s−1., 29.45 N, and 1.66 wt%.
Quantifying the effects of generalized (r,q) distribution function on modulational instability and rogue wave of electron acoustic solitons
Authors: Khan Abdullah , Abid Abid Ali , Khan Majid , Kengne Emmanuel
Published: December 2024

This paper presents a comprehensive analysis of modulational instability and super freak waves in an unmagnetized collisionless plasma consisting of hot and cold electron populations as described by a generalized distribution function. We employ the reductive perturbation method together with multiple-scale perturbations to derive the nonlinear Schr{"o}dinger equation governing the evolution of electron acoustic waves. This framework facilitates an inclusive investigation of the modulational instability of the electron acoustic waves, characterized by the dispersion and nonlinear coefficients of the derived equation. Our findings reveal the existence of electron acoustic envelope solitons, facilitating a clear distinction between stable and unstable regions based on established modulational instability criteria. Notably, the analytically evaluated growth rate of modulational instability demonstrates a strong dependence on the spectral indices of the generalized distribution function and the physical parameters of the plasma system. In this regard, we employ an accurate Darboux transformation scheme to derive the first- and higher-order rational solutions positioned on a nonzero background in the modulationally unstable region. This investigation further delves the features of super freak waves with extreme amplitude excitation and examine their dependences on the spectral indices, carrier wavenumber, hot-to-cold electron densities, and the temporal coordinate of the nonlinear Schr{"o}dinger equation. The study is supposed to enhance our understanding of the properties of electron acoustic solitary waves that may occur in non-Maxwellian space plasmas.
Passive on-chip isolators based on the thin-film lithium niobate platform
Authors: Liu Jiacheng , Xia Gongyu , Hong Qilin , Zhu Pingyu , Zhang KaiKai , Xia Keyu , Xu Ping , Qin Shiqiao , Zhu Zhihong
Published: December 2024

Optical isolators, the photonic analogs of electronic diodes, are essential for ensuring the unidirectional flow of light in optical systems, thereby mitigating the destabilizing effects of back reflections. Thin-film lithium niobate (TFLN), hailed as "the silicon of photonics," has emerged as a pivotal material in the realm of chip-scale nonlinear optics, propelling the demand for compact optical isolators. We report a breakthrough in the development of a fully passive, integrated optical isolator on the TFLN platform, leveraging the Kerr effect to achieve an impressive 10.3 dB of isolation with a minimal insertion loss of 1.87 dB. Further theoretical simulations have demonstrated that our design, when applied to a microring resonator with a Q factor of 5×106, can achieve 20 dB of isolation with an input power of merely 8 mW. This advancement underscores the immense potential of lithium niobate-based Kerr-effect isolators in propelling the integration and application of high-performance on-chip lasers, heralding a new era in integrated photonics.
Symmetry-protected and Brillouin zone folding driven bound states in the continuum in dielectric nanorod arrays for efficient third harmonic generation
Authors: Wang 王 Wen-Jing 文静 , Liang 梁 Shi-Jie 世杰 , Zou 邹 Jia-Qi 家祺 , Huo 霍 Yan-Yan 燕燕 , Ning 宁 Ting-Yin 廷银
Published: December 2024

Two types of bound states in continuum (BICs), symmetry-protected and Brillouin zone folding driven, are identified in hollow Si nanorod arrays. By modulating the direction and distance of the air holes from the center of the nanorods, it is possible to achieve either a single quasi-BIC or three quasi-BICs. The transmission spectra exhibit ultra-narrow lines, and the quasi-BICs demonstrate ultra-high Q factors. Additionally, efficient third-harmonic generation occurs at low pump intensities. The results indicate that the proposed nanostructures of two types of BICs with a flexible modulation hold great potential applications for nonlinear photonic devices.
Robust interpolation of EEG/MEG sensor time-series via electromagnetic source imaging
Authors: Cai Chang , Qi Xinbao , Long Yuanshun , Zhang Zheyuan , Yan Jing , Kang Huicong , Wu Wei , Nagarajan Srikantan S
Published: December 2024

Objective. electroencephalography (EEG) and magnetoencephalography (MEG) are widely used non-invasive techniques in clinical and cognitive neuroscience. However, low spatial resolution measurements, partial brain coverage by some sensor arrays, as well as noisy sensors could result in distorted sensor topographies resulting in inaccurate reconstructions of underlying brain dynamics. Solving these problems has been a challenging task. This paper proposes a robust framework based on electromagnetic source imaging for interpolation of unknown or poor quality EEG/MEG measurements. Approach. This framework consists of two steps: (1) estimating brain source activity using a robust inverse algorithm along with the leadfield matrix of available good sensors, and (2) interpolating unknown or poor quality EEG/MEG measurements using the reconstructed brain sources using the leadfield matrices of unknown or poor quality sensors. We evaluate the proposed framework through simulations and several real datasets, comparing its performance to two popular benchmarks—neighborhood interpolation and spherical spline interpolation algorithms. Results. In both simulations and real EEG/MEG measurements, we demonstrate several advantages compared to benchmarks, which are robust to highly correlated brain activity, low signal-to-noise ratio data and accurately estimates cortical dynamics. Significance. These results demonstrate a rigorous platform to enhance the spatial resolution of EEG and MEG, to overcome limitations of partial coverage of EEG/MEG sensor arrays that is particularly relevant to low-channel count optically pumped magnetometer arrays, and to estimate activity in poor/noisy sensors to a certain extent based on the available measurements from other good sensors. Implementation of this framework will enhance the quality of EEG and MEG, thereby expanding the potential applications of these modalities.
Low high-temperature hardness: a drawback of current ODS copper alloy Cu-Al2O3 applied in monoblock-type components fabricated by HIP
Authors: Peng Wu-Qingliang , Xu Yu-Ping , Du Fang-Yong , Tian Yu , Chen Zhen , Li Qiang , Luo Guang-Nan , Zhou Hai-Shan
Published: December 2024

Copper-based alloys, including precipitation hardened copper alloys and oxide dispersion strengthened (ODS) copper alloys, are considered highly promising heat sink materials for fusion divertor due to their excellent thermal conductivity and high strength. In this work, components consisting of five tungsten monoblocks and utilizing ODS copper alloy Cu-Al2O3 (GlidCop Al-15) were successfully manufactured via the hot isostatic pressing (HIP) technique. Plastic deformation with an average twisting degree of 22° and circular indentations with an average depth of 88.33 μm were observed at the toroidal gap of the W/Cu/GlidCop Al-15 mock-up, compared to a twisting degree of 0° and a depth of 35.55 μm in a similarly manufactured W/Cu/CuCrZr mock-up. High heat flux (HHF) thermal fatigue tests at 15 MW m−2 were conducted to evaluate the durability of the components. Unexpectedly, premature leakage failure occurs at the same toroidal gap. The relatively lower hardness of GlidCop Al-15 (14.90 ± 1.76 HV at 680 °C) at high temperatures compared with CuCrZr (45.34 ± 1.77 HV at 680 °C) has been identified as the primary factor leading to easy circular indentation at the toroidal gap during the HIP fabrication process, thereby increasing the likelihood of crack initiation under cyclic HHF loading conditions. This paper presents a new perspective on the application and performance enhancement of ODS copper alloy Cu-Al2O3 in the manufacturing of divertor components.
First Principle Investigations of K doped CuInSe2 for Optoelectronic Applications
Authors: Sharma S , Soni A , Sahariya J , Rangar K , Rawat K
Published: December 2024

CuInSe2 is a ternary compound and a fine viable substitute of polycrystalline silicon for photovoltaic applications. In this work we computationally investigated the consequence of K atom doping in CuInSe2. The structural, electronic, and optical features of the K doped CuInSe2 compound was calculated using the full potential linearized augmented plane wave approach (FP-LAPW). Furthermore, the Wien2k algorithm performs the most accurate Tran-Blaha modified Becke-Johnson (TB-mBJ) exchange approximation. To ascertain the adaptability of compound under study, optical parameters including the real and imaginary dielectric tensor, absorption coefficient, reflectivity, and refractivity are computed. For Cu0.8125K0.1875InSe2, the energy band gap value revealed via TB-mBJ is 1.07eV. According to states adding K doping to the Cu site in CuInSe2 improves the band gap value, indicating its potential use in solar devices. The compound acquired optical and electronic properties significantly implied that it would be useful in optoelectronic applications.
Textile patch antenna using fleece and felt substrates
Authors: Azahari BA , Kamardin K , Yamada Y , Fitri S
Published: December 2024

The application of textile patch antennas can be realized by integrating high-gain antennas into clothing, offering innovative solutions for wearable technology. For example, patients clothing where it can transmit the data from the heart monitoring wirelessly. This study explores the main aspects of the textile patch antenna using fleece and felt substrates. The electromagnetic simulation of the calculated parameters for the patch antenna, the fabrication method for fleece and felt substrates using conductive copper paint for both the patch and the ground plane or conductive material part, and the measurement process for the fabricated antennas. Measurements were carried out using a Vector Network Analyzer (VNA) for input impedance and an anechoic chamber for assessing radiation patterns and gain. The results from the electromagnetic simulations and measurements showed good agreement, except for the gain of the felt antenna, which may be attributed to either a faulty felt antenna or measurement error.
A xenogenic-free culture medium for cell micro-patterning systems as cell-instructive biomaterials for potential clinical applications
Authors: Che Hui , Hart Melanie L , Lauer Jasmin C , Selig Mischa , Voelker Marita , Kurz Bodo , Rolauffs Bernd
Published: December 2024

Cell micro-patterning controls cell fate and function and has potential for generating therapeutically usable mesenchymal stromal cell (MSC) populations with precise functions. However, to date, the micro-patterning of human cells in a translational context has been impossible because only ruminant media supplements, e.g. fetal bovine serum (FBS), are established for use with micro-patterns (MPs). Thus, there are currently no good manufacturing practice (GMP)-compliant media available for MPs. This study tested a xenogenic-free human plasma and platelet lysate (hP + PL) medium supplement to determine its compatibility with MPs. Unfiltered hP + PL medium resulted in significant protein deposition, creating a ‘carpet-like’ layer that rendered MPs ineffective. Filtration (3×/5×) eliminated this effect. Importantly, quantitative comparison using droplet digital PCR revealed that human MSCs in all media types exhibited similar profiles with strong myogenic Calponin 1/Transgelin 2 (TAGLN2) and weaker osteogenic alkaline phosphatase/Runt-related transcription factor 2 marker expression, and much weaker adipogenic (lipoprotein lipase/peroxisome proliferator-activated receptor gamma) and chondrogenic (collagen type II/aggrecan) expression, with profiles being dominated by myogenic markers. Within these similar profiles, an even stronger induction of the myogenic marker TAGLN2 by all hP + PL- compared to FBS-containing media. Overall, this suggested that FBS can be replaced with hP + PL without altering differentiation profiles. However, assessing individual MSC responses to various MP types with defined categories revealed that unfiltered hP + PL medium was unusable. Importantly, FBS- and 3× filtered hP + PL media were comparable in each differentiation category. Summarized, this study recommends 3× filtered hP + PL as a xenogenic-free and potentially GMP-compliant alternative to FBS as a culture medium supplement for micro-patterning cell populations in both basic and translational research that will ensure consistent and reliable MSC micro-patterning for therapeutic use.
Thawing permafrost is subsiding in the Northern Hemisphere—review and perspectives
Authors: Streletskiy Dmitry A , Maslakov Alexey , Grosse Guido , Shiklomanov Nikolay I , Farquharson Louise , Zwieback Simon , Iwahana Go , Bartsch Annett , Liu Lin , Strozzi Tazio , Lee Hanna , Debolskiy Matvey V
Published: December 2024

High-latitude and altitude cold regions are affected by climate warming and permafrost degradation. One of the major concerns associated with degrading permafrost is thaw subsidence (TS) due to melting of excess ground ice and associated thaw consolidation. Field observations, remote sensing, and numerical modeling are used to measure and estimate the extent and rates of TS across broad spatial and temporal scales. Our new data synthesis effort from diverse permafrost regions of North America and Eurasia, confirms widespread TS across the panarctic permafrost domain with rates of up to 2 cm yr−1 in the areas with low ice content and more than 3 cm yr−1 in regions with ice-rich permafrost. Areas with human activities or areas affected by wildfires exhibited higher subsidence rates. Our findings suggest that permafrost landscapes are undergoing geomorphic change that is impacting hydrology, ecosystems, and human infrastructure. The development of a systematic TS monitoring is urgently needed to deliver consistent and continuous exchange of data across different permafrost regions. Integration of coordinated field observations, remote sensing, and modeling of TS across a range of scales would contribute to better understanding of rapidly changing permafrost environments and resulting climate feedbacks.
The impact of the AMO on wintertime surface wind speed reversal in Northeast Asia
Authors: Luo Neng , Ding Ruiqiang
Published: December 2024

Decadal variations in seasonal mean surface wind speed (SWS) and their underlying causes remain elusive. Here, we utilize wind data from in situ stations to demonstrate that the stilling reversed around 2002 and that wintertime wind speed in Northeast Asia has rebounded. We illustrate that decadal-scale variations of SWS are closely linked to the phase shift of the Atlantic Multidecadal Oscillation (AMO). Specifically, an AMO positive phase generates a wave train characterized by a cyclonic anomaly over Northeast Asia, which leads to the strengthened westerly wind, enhanced meridional temperature gradient, and increased transient eddy activities in Northeast Asia. These findings hold vital implications for considering changes in the AMO to gain a comprehensive understanding of SWS variations at the regional scale.