bluuebunny/crossref_metadata_2025_split huggingface dataset:
Role of complexity on the minimal deformation of black holes
Authors: Yousaf Z , Bamba Kazuharu , Almutairi Bander , Khan S , Bhatti M Z 
Published: July 2024

Abstract
We investigate spherically symmetric classes of anisotropic solutions within the realm of a schematic gravitational decoupling scheme, primarily decoupling through minimal geometric deformation, applied to non-rotating, ultra-compact, self-gravitational fluid distributions. In this respect, we employ the minimal complexity factor scheme to generate physically realistic models for anisotropic matter distributions, using a well-behaved model. The zero-complexity factor condition enables us to determine the deformation function for solving the decoupled system. We explore all the structure-defining scalar variables, such as density inhomogeneity, strong energy condition, density homogeneity, and the complexity factor (an alloy of density inhomogeneity and pressure anisotropy) for the decoupling constant ranging between 0 and 1. We observe that the anisotropy vanishes when the coupling constant is set to unity. This finding holds significance as it implies that, in the context of a zero-complexity factor approach, an anisotropic matter distribution becomes perfect without requiring any isotropy requirements. This work effectively explored the impact of complexity on the composition of self-gravitational stellar distributions. This effective approach enables the development of new, physically realistic isotropic stellar models for anisotropic matter distributions. Additionally, our findings indicate that the complexity factor in static, spherically symmetric self-gravitational objects can significantly affect the nature of the matter distribution within these systems. It is concluded that the minimally deformed Durgapal-IV model features an increasing pressure profile, and the local anisotropy of pressure vanishes throughout the model under complexity-free conditions.
Imprints of the operator ordering ambiguity on the dynamics of perfect fluid dominated quantum Universe
Authors: Sahota Harkirat Singh 
Published: July 2024

Abstract
Sharply peaked quantum states are conjectured to be conducive to the notion of a quantum-corrected spacetime. We investigate this conjecture for a flat-FLRW model with perfect fluid, where a generalized ordering scheme is considered for the gravitational Hamiltonian. We study the implications of different ordering choices on the dynamics of the quantum Universe. We demonstrate that the imprints of the operator ordering ambiguity are minimal, and quantum fluctuations are small in the case of sharply peaked states, leading to a consistent notion of a quantum-corrected spacetime defined via the expectation value of the scale factor. Surprisingly, the ordering imprints survive far away from the singularity through the quantum fluctuations in the quantum-corrected spacetime for broadly peaked states.
Doppler sensitivity and resonant tuning of Rydberg atom-based antennas
Authors: Weichman Peter B 
Published: July 2024

Abstract
Radio frequency antennas based on Rydberg atom vapor cells can in principle reach sensitivities beyond those of any conventional wire antenna, especially at lower frequencies where very long wires are needed to accommodate the increasing wavelength. They also have other desirable features such as consisting of nonmetallic, hence lower profile, elements. This paper presents a detailed theoretical investigation of Rydberg antenna sensitivity, elucidating parameter regimes that could cumulatively lead to a sensitivity increase 2–3 orders of magnitude beyond that of currently tested configurations. The key insight is to optimally combine the advantages of two well-studied approaches: (i) three laser ‘2D star configuration’ setups that, when enhanced with increased laser power, to some degree compensate for atom motion-induced Doppler broadening, and (ii) resonant coupling between a pair of near-degenerate Rydberg levels, tuned via a local oscillator to the incident signal of interest. The advantage of the star setup is subtle because it only restores the overall sensitivity to the expected Doppler-limited value, compensating for additional significant off-resonance reductions where differently moving atom sub-populations destructively interfere with each other in the net signal. An additional unique advantage of local oscillator tuning is that it leads to vastly narrower line widths, as low as ∼10 kHz set by the intrinsic Rydberg state lifetimes, rather than the typical ∼10 MHz scale set by the core state lifetimes. Intuitively, with this setup the two Rydberg states may be tuned to act as an independent high-q cavity, a point of view supported by a study of the frequency-dependence of the antenna resonant response. There are a number of practical experimental advances, especially larger ∼1 cm laser beam widths, required to suppress various extrinsic line broadening effects and to fully exploit this ‘Rydberg superheterodyne’ response.
Field management in NiO
x
/β-Ga2O3 merged-PIN Schottky diodes: simulation studies and experimental validation
Authors: Vasquez Jose Manuel Taboada , Mukherjee Ankita , Singh Smriti , Khandelwal Vishal , Yuvaraja Saravanan , Maciel Garcia Glen Isaac , Rajbhar Manoj , Li Xiaohang , Sarkar Biplab 
Published: July 2024

Abstract
In recent years, p-type NiO
x
has emerged as a promising alternative to realize kilovolt-class β-Ga2O3-based PN junction diodes. However, only a handful of studies could realize β–Ga2O3-based unipolar diodes using NiO
x
as a guard ring or floating rings. In this work, we investigate the device design of NiO
x
/β-Ga2O3 unipolar diodes using the technology computer aided design simulations and experimental validations. We show that a systematic electric field management approach can potentially lead to NiO
x
/β-Ga2O3 heterojunction unipolar diode and offer enhanced breakdown characteristics without a severe compromise in the ON-state resistance. Accordingly, the NiO
x
/β-Ga2O3 heterojunction diode in the merged-PIN Schottky configuration is shown to outperform the regular Schottky diode or junction barrier Schottky diode counterpart. The analysis performed in this work is believed to be valuable in the device design of β-Ga2O3-based unipolar diodes that use a different p-type semiconductor candidate as guard rings and floating rings.
Saturable absorption properties of mixed lead-tin halide perovskites and their application in near-infrared ultrafast lasers
Authors: Lan Xinru , Yang Cheng , Wei Chengming , Liu Jiabao , Zhang Zeyu , Chen Zhengwei , Wang Xu , Hu Ziyang 
Published: July 2024

Abstract
Mixed lead–tin halide perovskites, as highly sensitive materials in the near-infrared region, hold significant potential for optoelectronic device applications. Here, mixed lead–tin halide perovskite saturable absorbers (SAs) have been developed by coupling with the side-polished surfaces of the single-mode fibers and excellent saturable absorption effects of the mixed lead–tin halide perovskite SAs have been demonstrated in the near-infrared region. By constructing the in-gap site assisted carrier transfer mode, the saturation absorption process of the mixed lead–tin halide perovskite SAs can be well explained, in which defects as in-gap sites can help the photon-generated carriers transfer into the conduction band and promote the Pauli-blocking-induced absorption bleaching in the SA. Moreover, ytterbium-doped fiber lasers based on perovskite SAs have been fabricated, and mode-locked operations at 1040 nm are achieved using the mixed lead–tin halide perovskite SA, generating ultra-short pulses with a pulse width of 683 fs, 3 dB bandwidth of 4.88 nm, signal-to-noise ratio exceeding 49.74 dB, and a repetition rate of 3.74 MHz. Our findings demonstrate that the mixed lead–tin halide perovskite SAs have excellent optical modulation capability and promising applications in the field of ultrafast photonics.
Enhanced flexoelectricity of liquid with hydrated ions
Authors: Li Yifan , Li Yanyu , Feng Xingjian , Zhai Chongpu , Zhang Shuwen , Xu Minglong 
Published: July 2024

Abstract
Flexoelectricity, denoted as an electromechanical coupling effect from strain gradient introduced polarization, is prevalent in dielectric materials. However, its application in low-viscosity liquids has been limited by the scale of the flexoelectric coefficient. This study explores the flexoelectric coefficient of various hydrated ion solutions through a series of experiments. Additionally, the interplay between ion adsorption and the flexoelectric effect is investigated by using interfacial voltage detection. By introducing hydrated structures into liquids, a significant enlargement of the flexoelectric coefficient up to 2.3 × 10−9 C m−1 is obtained in Fe2(SO4)3 solution by four times than DI water. These findings highlight the remarkable electromechanical properties of liquid materials with hydrated ions and suggest promising avenues for the application of liquid dielectrics in hydrovoltaic technology, ionotronic devices, and energy harvesters.
Extended Fayans energy density functional: optimization and analysis
Authors: Reinhard Paul-Gerhard , O’Neal Jared , Wild Stefan M , Nazarewicz Witold 
Published: July 2024

Abstract
The Fayans energy density functional (EDF) has been very successful in describing global nuclear properties (binding energies, charge radii, and especially differences of radii) within nuclear density functional theory. In a recent study, supervised machine learning methods were used to calibrate the Fayans EDF. Building on this experience, in this work we explore the effect of adding isovector pairing terms, which are responsible for different proton and neutron pairing fields, by comparing a 13D model without the isovector pairing term against the extended 14D model. At the heart of the calibration is a carefully selected heterogeneous dataset of experimental observables representing ground-state properties of spherical even–even nuclei. To quantify the impact of the calibration dataset on model parameters and the importance of the new terms, we carry out advanced sensitivity and correlation analysis on both models. The extension to 14D improves the overall quality of the model by about 30%. The enhanced degrees of freedom of the 14D model reduce correlations between model parameters and enhance sensitivity.
First-principles calculation of Hubbard U for Terbium metal under high pressure
Authors: Burnett Logan A , Clay Matthew P , Vohra Yogesh K , Chen Cheng-Chien 
Published: July 2024

Abstract
Using density functional theory (DFT) and linear response approaches, we compute the on-site Hubbard interaction U of elemental Terbium (Tb) metal in the pressure range ∼ 0–65 GPa. The resulting first-principles U values with experimental crystal structures enable us to examine the magnetic properties of Tb using a DFT+U method. The lowest-energy magnetic states in our calculations for different high-pressure Tb phases—including hcp, α-Sm, and dhcp—are found to be compatible with the corresponding magnetic ordering vectors reported in experiments. The result shows that the inclusion of Hubbard U substantially improves the accuracy and efficiency in modeling correlated rare-earth materials. Our study also provides the necessary U information for other quantum many-body techniques to study Tb under extreme pressure conditions.
Enhanced feature extraction YOLO industrial small object detection algorithm based on receptive-field attention and multi-scale features
Authors: Tao Hongfeng , Zheng Yuechang , Wang Yue , Qiu Jier , Stojanovic Vladimir 
Published: July 2024

Abstract
To guarantee the stability and safety of industrial production, it is necessary to regulate the behavior of employees. However, the high background complexity, low pixel count, occlusion and fuzzy appearance can result in a high leakage rate and poor detection accuracy of small objects. Considering the above problems, this paper proposes the Enhanced feature extraction-You Only Look Once (EFE-YOLO) algorithm to improve the detection of industrial small objects. To enhance the detection of fuzzy and occluded objects, the PixelShuffle and Receptive-Field Attention (PSRFA) upsampling module is designed to preserve and reconstruct more detailed information and extract the receptive-field attention weights. Furthermore, the multi-scale and efficient (MSE) downsampling module is designed to merge global and local semantic features to alleviate the problem of false and missed detection. Subsequently, the Adaptive Feature Adjustment and Fusion (AFAF) module is designed to highlight the important features and suppress background information that is not beneficial for detection. Finally, the EIoU loss function is used to improve the convergence speed and localization accuracy. All experiments are conducted on homemade dataset. The improved YOLOv5 algorithm proposed in this paper improves mAP@0.50 (mean average precision at a threshold of 0.50) by 2.8% compared to the YOLOv5 algorithm. The average precision and recall of small objects show an improvement of 8.1% and 7.5%, respectively. The detection performance is still leading in comparison with other advanced algorithms.
Equivalent circuit fitting method for microwave characterisation of low-k dielectric thin films
Authors: Guerenneur A , Kouznetsov D , Narducci D , Luciano F , Sun X , Van Dorpe P , Ciubotaru F , Adelmann C 
Published: July 2024

Abstract
A new equivalent circuit fitting analysis scheme is proposed to analyse the measured data of test structures originally developed to characterise high-κ dielectrics at frequencies up to 5 GHz (Zhengxiang et al 1998 IEEE Trans. Electron Devices
45 1811–6). It is compared to an extension of the analysis which can be used for high-κ dielectrics at up to 50 GHz (Rundqvist et al 2004 Integr. Ferroelectr.
60 1–19). The proposed scheme focuses on the accurate characterisation of low-κ dielectrics, which exhibit greater sensitivity to various parasitics. The scheme utilises the same concentric capacitor devices and measurement setup as the original method, maintaining the advantage of ease in fabrication of the original approach. The physical model employed in the analysis step of the original method, which tended to overestimate the dielectric permittivity, has been enhanced by incorporating fringing fields and a parasitic gap capacitance as circuit elements. The accuracy of the new approach is validated using experimental data, demonstrating its ability to more accurately determine the dielectric permittivity compared to the original method.
Rare earth oxide Y2O3 modified g-C3N4 for efficient photocatalytic hydrogen production: photocatalytic performance and electron transfer channels
Authors: Niu Fengyan , Zhang Ziyang , Lei Weiyan , Li Jiashuang , Wang Baoxiang , Shen Yi 
Published: July 2024

Abstract
This work used a one-step calcination process to prepare g-C3N4 composites with varying Y2O3 loading. XRD, TEM, and XPS verified the structure and morphology of the composite photocatalyst, and its photoelectrochemical and hydrogen production performance were studied. According to the experimental results, it is found that the composite structure between Y2O3 and g-C3N4 effectively suppresses the photoelectron–hole complex and enhances the photocatalytic hydrogen production properties of g-C3N4. Under the irradiation of a 300 W xenon lamp, YCN-3 had superior photocatalytic hydrogen generation performance, achieving a rate of 1079.61 μmol g−1 h−1, which was 2.3 times greater than that of g-C3N4 in its unmodified state. After three consecutive photocatalytic operations, satisfactory stability and reusability were obtained. Finally, the possibility of a mechanism for the photocatalytic charge transfer pathway is discussed, which provides an effective way for g-C3N4 photocatalytic hydrogen production.
Thermal-electrical analogy for simulations of superconducting power cables
Authors: de Sousa Wescley T B , Kottonau Dustin , Murta-Pina João , Morandi Antonio , Noe Mathias 
Published: July 2024

Abstract
Due the integration of superconducting technologies into electrical networks around the world, its precise simulations in power grids are increasingly becoming a desirable outcome. Over the years, sophisticated methods have been used to model superconducting power cables and, in this way, predict its behavior under different conditions. Most of the available models, however, are not advisable to be used and embedded in power system simulators. In this manuscript, we focus on the development of a method specifically for modeling superconducting cables in traditional power grid simulators. We start developing the model through a case example, within the basic concepts are introduced and later expanded to general cases. The model also incorporates the transient behavior of the cooling media, which is mandatory for such cables. It has been observed that the proposed model requires less computational effort and is able to deliver accurate results when compared to more advanced methods.
Topological insulator based axial superconducting quantum interferometer structures
Authors: Zimmermann Erik , Rehman Jalil Abdur , Schleenvoigt Michael , Karthein Jan , Frohn Benedikt , Behner Gerrit , Lentz Florian , Trellenkamp Stefan , Neumann Elmar , Schüffelgen Peter , Lüth Hans , Grützmacher Detlev , Schäpers Thomas 
Published: July 2024

Abstract
Nanoscale superconducting quantum interference devices are fabricated in-situ from a single Bi0.26Sb1.74Te3 nanoribbon that is defined using selective-area growth and contacted with superconducting Nb electrodes via a shadow mask technique. We present

h

/

(
2
e
)

magnetic flux periodic interference in both, fully and non-fully proximitized nanoribbons. The pronounced oscillations are attributed to interference effects of coherent transport through the topological surface states encompassing the cross-section of the nanoribbon.
The A-15-type superconducting hydride La4H23: a nanograined structure with low strain, strong electron-phonon interaction, and a moderate level of nonadiabaticity
Authors: Talantsev Evgeny F , Chistyakov Vasiliy V 
Published: July 2024

Abstract
For seven decades, when referring to A-15 superconductors, we meant metallic A3B alloys (where A is a transition metal, and B is group IIIB and IVB elements) discovered by Hardy and Hulm (1953 Phys. Rev.
89 884). Nb3Ge exhibited the highest superconducting transition temperature, Tc
= 23K, among these alloys. One of these alloys, Nb3Sn, is the primary material in modern applied superconductivity. Recently, Guo et al (2024 Natl Sci. Rev. nwae149, https://doi.org/10.1093/nsr/nwae149) extended the family of superconductors where the metallic ions are arranged in the beta tungsten (A-15) sublattice by observation of Tc

,zero = 81K in the La4H23 phase compressed at P = 118 GPa. Despite the fact that La4H23 has much lower Tc
in comparison with the near-room-temperature superconducting LaH10 phase (Tc

,zero = 250K at P ∼ 200 GPa) discovered by Drozdov et al (2019 Nature
569 531), La4H23 holds the record for the highest Tc
within the A-15 family. Cross et al (2024 Phys. Rev. B 109 L020503) confirmed the high-temperature superconductivity in compressed La4H23. In this paper, we analyzed available experimental data measured in La4H23 and found that this superconductor exhibits a nanograined structure, 5.5 nm ⩽ D ⩽ 35 nm, low crystalline strain,

|

ε

|

⩽ 0.003, strong electron–phonon interaction, 1.5 ⩽ λe-ph⩽ 2.55, and a moderate level of nonadiabaticity, 0.18 ⩽ Θ
D
/T
F ⩽ 0.22 (where Θ
D
is the Debye temperature, and T
F is the Fermi temperature). We found that the derived Θ
D
/T
F and Tc
/T
F values for the La4H23 phase are similar to those in MgB2, cuprates, pnictides, and the near-room-temperature superconductors H3S and LaH10.

To the memory of Martin J. Ryan, man and scientist who taught EFT the intricacies of X-ray diffraction.
Laser powered dissipative quantum batteries in atom-cavity QED
Authors: Beleño Zamir , Santos Marcelo F , Barra Felipe 
Published: July 2024

Abstract
The interaction of a three-level atom with the electromagnetic field of a quantum cavity in the presence of a laser field presents a rich behavior in the dispersive regime that we exploit to discuss two quantum batteries. In the first setup, we consider a single three-level atom interacting sequentially with many cavities, each in a thermal state. We show that under this process, the atom converges towards an equilibrium state that displays population inversion. In the second setup, a stream of atoms in a thermal state interacts sequentially with a single cavity initially in a thermal state at the same temperature as the atoms. We show that the cavity’s energy increases continuously as the stream of atoms continues to cross, and the cavity does not reach an equilibrium state. After many atoms have traveled, the cavity’s state becomes active, storing extractable energy that increases in proportion to the work done by the laser. However, the same dynamics may involve only two cavity levels in an interesting limit called the highly selective regime. In that regime, the cavity reaches an equilibrium state similar to the one of the atom in the first scenario. The charging process we propose is robust. We discuss its thermodynamics and evaluate the energy supplied by the laser, the energy stored in the battery, and, thus, the device’s efficiency. We also analyze the role of damping.
Exact moments for trapped active particles: inertial impact on steady-state properties and re-entrance
Authors: Patel Manish , Chaudhuri Debasish 
Published: July 2024

Abstract
In this study, we investigate the behavior of inertial active Brownian particles in a d-dimensional harmonic trap in the presence of translational diffusion. While the solution of the Fokker–Planck equation is generally challenging, it can be utilized to compute the exact time evolution of all time-dependent dynamical moments using a Laplace transform approach. We present the explicit form for several moments of position and velocity in d-dimensions. An interplay of time scales assures that the effective diffusivity and steady-state kinetic temperature depend on both inertia and trap strength, unlike passive systems. The distance from equilibrium, measured by the violation of equilibrium fluctuation-dissipation and the amount of entropy production, decreases with increasing inertia and trap strength. We present detailed ‘phase diagrams’ using kurtosis of velocity and position, showing possibilities of re-entrance to equilibrium.
Exploring the dynamic interplay of intermodal and higher order dispersion in nonlinear negative index metamaterials
Authors: Veni S Saravana , Mani Rajan M S , Biswas Anjan , Alshomrani Ali Saleh 
Published: July 2024

Abstract
Our study delves into the intricate interplay of various factors within metamaterials, with a focus on modulation instability. Through our research, we elucidate the intricate dynamics involving intermodal dispersion, self-steepening effect, higher order dispersion, and plane wave amplitude, showcasing their competition and influence on modulation instability phenomena. We aim to explore the impact of intermodal dispersion and higher-order effects by numerically solving the generalized nonlinear Schrödinger equation (NLSE), which models the propagation of a few-cycle pulse in a nonlinear metamaterial. Our modulation instability (MI) analysis captures the complex dynamics these factors introduce. We demonstrate the spatiotemporal evolution of MI under different parameter values, revealing how these variations influence the instability’s development and characteristics. This approach provides a detailed understanding of the system’s behavior across various conditions, highlighting the roles of intermodal dispersion and higher-order effects. We demonstrate that the behavior of modulation instability bands and their reliance on parameters such as self-steepening and wave amplitude is contingent upon the specific characteristics of the optical setup and medium dispersion properties