bluuebunny/crossref_metadata_2025_split huggingface dataset:
Frequency reconfigurable slot antenna utilizing solid-state plasma S-PIN diodes: simulation and experimental analysis
Authors: Jin Xiangyu , Zhou Yonggang , Lou Jian , Liu Siyuan , Liu Shaobin 
Published: July 2024

Abstract
This article examines the feasibility of integrating solid-state plasma surface p-i-n (S-PIN) diodes into on-chip slots using silicon-on-insulator technology. Two categories of solid-state plasma S-PIN diodes are characterized. Simulations analyze the current–voltage (I–V) characteristics, carrier concentrations, potential distribution, and thermal considerations of both single and dual S-PIN diodes, with optimization of their structural parameters and sizes. Experimental tests on fabricated S-PIN diodes of varying sizes with bias lines embedded in the on-chip slots show favorable I–V characteristics for both types of diodes. The measured results closely align with simulation predictions for the diodes’ conduction onset voltages. Additionally, a cavity-backed slot antenna is proposed to evaluate and compare radiation characteristics resulting from integrating different types of S-PIN diodes.
Breakup dynamics of a neutron-halo projectile on heavy target at deep sub-barrier energies
Authors: Mukeru B , Sithole T , Tomio Lauro 
Published: July 2024

Abstract
By studying the total fusion and breakup cross-sections in the interaction of the neutron-halo 11Be projectile on the lead target 208Pb, it is shown that, even for the neutron-halo projectile, the breakup channel remains the most dominant reaction channel at sub-barrier energies, following a characteristic behavior that was also previously verified for the case of the proton-halo projectile 8B. This feature is found to emanate from the enhancement of the breakup cross-section, due to the continuum–continuum couplings (CCC) coming exclusively from its Coulomb component. We further speculate that the enhancement of the Coulomb breakup cross-section at sub-barrier incident energies by the CCC could be associated with the projectile breaking up on the outgoing trajectory, provided these couplings can be proven to delay the breakup process.
Threshold temperature of superfluorescence generation in CuCl quantum dots under resonant excitation of excitons and resonant two-photon excitation of biexcitons
Authors: Kawamura Kohei , Yoshida Tomoharu , Ishihara Jun , Ishikawa Akira , Miyajima Kensuke 
Published: July 2024

Abstract
We studied the threshold temperature of superfluorescence (SF) generation with regard to biexcitons in CuCl quantum dots (QDs) under resonant two-photon excitation of biexcitons and resonant excitation of excitons to demonstrate the influence of initial population densities in the QDs on SF generation. As a result, the threshold temperature under the resonant excitation of excitons was higher than that under the two-photon excitation of biexcitons. This indicates that the high density of excited dots facilitates the rapid establishment of coherence among the dots, overcoming disadvantages of incomplete population inversion and formation process of biexcitons. We performed a theoretical calculation of the time profiles of the biexcitonic emission based on semiconductor luminescence equations. The experimentally obtained temperature dependence of the time profiles was qualitatively reproduced by calculating their dependence on the dephasing rate. In addition, we estimated the temperature dependence of the phase relaxation time of the biexcitons in the CuCl QDs by analyzing the temperature dependence of SF.
An investigation of shaft voltage in synchronous generators under SAGE and variable load condition
Authors: Sun Kai , He Yu-Ling , Wu Xue-wei , Luo Hao-ran , Jiao Ling-yu , Gerada David 
Published: July 2024

Abstract
Synchronous generators are widely used in power generation systems. Static air-gap eccentricity (SAGE) often occurs in synchronous generators due to the component wear over prolonged operation. This paper presents a comprehensive mathematical model specifically tailored for SAGE fault, incorporating for the influence of stator slotting. The study thoroughly examines the impacts of both eccentricity and varying loads on the shaft voltage using the developed model. Furthermore, a novel method for detecting SAGE is introduced, leveraging the mathematical model of shaft voltage. This detection method proves effective for identifying eccentricity in synchronous generators across different load conditions by reasonably combining shaft voltage and phase current. The mathematical model of shaft voltage and the proposed detection method are validated through three-dimensional finite-element calculations and experimental studies. The work is helpful to manage and predict the shaft voltage. This paper contributes to the prevention of shaft voltage damage and real-time monitoring of the SAGE fault in synchronous generators.
Sparse reservoir computing with vertically coupled vortex spin-torque oscillators for time series prediction
Authors: Shen Haobo , Xu Lie , Jin Menghao , Li Hai , Yu Changqiu , Liu Bo , Zhou Tiejun 
Published: July 2024

Abstract
Spin torque nano-oscillators possessing fast nonlinear dynamics and short-term memory functions are potentially able to achieve energy-efficient neuromorphic computing. In this study, we introduce an activation-state controllable spin neuron unit composed of vertically coupled vortex spin torque oscillators and a V–I source circuit is proposed and used to build an energy-efficient sparse reservoir computing (RC) system to solve nonlinear dynamic system prediction task. Based on micromagnetic and electronic circuit simulation, the Mackey–Glass chaotic time series and the real motor vibration signal series can be predicted by the RC system with merely 20 and 100 spin neuron units, respectively. Further study shows that the proposed sparse reservoir system could reduce energy consumption without significantly compromising performance, and a minimal response from inactivated neurons is crucial for maintaining the system’s performance. The accuracy and signal processing speed show the potential of the proposed sparse RC system for high-performance and low-energy neuromorphic computing.
Atmospheric neutron-induced single event burnout characterization of 4.5 kV Si IGBTs with spallation neutron irradiation
Authors: Peng Chao , Yang Liu , Lei Zhifeng , Zhou Yuebin , Ma Teng , Yuan Zhiyong , Zhang Zhangang , He Yujuan , Huang Yun 
Published: July 2024

Abstract
The atmospheric neutron-induced single event burnout (SEB) is observed for 4.5 kV Si IGBTs with trench gate structure by conducting spallation neutron source irradiation. The SEB is manifested as a random failure and is strongly related to the bias voltage. The SEB failure rates of two different Si IGBTs at different bias voltages are calculated based on the experimental results. It shows that the failure rates increase exponentially with bias voltages. For two different kinds of IGBTs, the atmospheric neutron-induced failure rate at an altitude of 4000 m is 0.855 FIT and 4.39 FIT, respectively, when biased at 60% of the rated voltage. When the bias voltage is increased to 64% of the rated voltage, the corresponding failure rates are increased to 24.7 FIT and 47.6 FIT. Furthermore, the SEB mechanisms for Si IGBTs are investigated by TCAD simulations.
Performance of surge-induced synchronized switch harvesting on inductor as an efficient technique under strong electromechanical coupling and low amplitudes of vibration
Authors: Onoda Junjiro , Minesugi Kenji 
Published: July 2024

Abstract
The process of harvesting energy from ambient sources is key for various applications. This study examined the performance of two representative techniques from the surge-induced synchronized switch harvesting on inductor (S3HI) family under strong electromechanical coupling and compared this performance with that of some established techniques. S3HI techniques exploit the surge voltage to overcome the voltage barrier of diodes for rectifiers and storage capacitor voltages. One of their features, revealed in a previous study on weakly coupled systems, is that they can harvest substantial energy from low-level vibrations. This feature is desirable for certain use cases. This study aimed to clarify whether this feature is applicable even when the coupling is strong. The performance of various established techniques and two representatives from the S3HI group was studied by formulating an approximate analytical solution and performing numerical simulations and experiments. The theoretical results were confirmed to be consistent, and the discrepancy between experimental and theoretical results was minor. These results clearly demonstrate that the techniques from the S3HI family can effectively harvest substantial energy from small-amplitude vibrations, even when the coupling is strong. Moreover, the performance advantage of S3HI methods is even greater when the coupling is strong.
A nonlinear piezoelectric shunt absorber with tunable piecewise linear negative capacitance
Authors: Zhang Lin , Li Ming , Sun Xiaoming , Cheng Wei 
Published: July 2024

Abstract
In recent years, extensive research has been devoted to nonlinear piezoelectric shunt circuits for mitigating structural vibrations. However, existing studies have primarily concentrated on polynomial nonlinearity, particularly cubic nonlinearity. This paper develops a tunable non-smooth piezoelectric shunt absorber to suppress structural vibrations under harmonic excitation. We enhance the conventional resonant circuit by introducing a piecewise linear negative capacitor, which is implemented using a pair of diodes and voltage sources. The stationary response of the non-smooth system is derived using the complexification–averaging method. The effects of critical voltage and excitation intensity on the damping performance are investigated subsequently. Furthermore, we apply an adaptive control method based on the gradient descent algorithm with adaptive moment estimation (Adam) to the nonlinear circuit, improving its damping performance and enabling adaptation to changes in excitation intensity. Experimental results validate the effectiveness of the proposed adaptive nonlinear circuit, demonstrating superior stationary performance compared to linear resonant shunt circuits across a broad bandwidth of frequencies, especially at off-resonant frequencies.
Development and testing of a discrete coil magnetostrictive actuator
Authors: Wang Yanwen , Zhu Yuchuan , Chen Long , Ling Jie , Zhang Mingming 
Published: July 2024

Abstract
Active combustion control (ACC) technology is an effective measure for suppressing the combustion oscillation of aero-engines. The magnetostrictive actuator is the most suitable choice for the ACC actuator due to its excellent high-frequency characteristics and high-temperature resistance. In order for the magnetostrictive actuator to produce high-frequency displacement, the constant current driver must have sufficient power, which results in a larger mass of the driver. A solution is to use multi-channel and low-power constant current driver. Therefore, the coil of the magnetostrictive actuator is axially dispersed and driven by two four-channel servo amplifiers. The driver’s mass is significantly reduced while maintaining the same electromagnetic conversion effect. In addition, an analytical model of a discrete coil magnetostrictive actuator is established, and a series of experiments are conducted. The maximum hysteresis error of output displacement at 200 Hz is reduced by 15.2%. Furthermore, under PID closed-loop control, the root mean square (RMS) error is less than 2% when tracking a 10 Hz sinusoidal displacement with coil switching drive.
Applicability of measurement-based quantum computation towards physically-driven variational quantum eigensolver
Authors: Qin Zheng , Li Xiufan , Zhou Yang , Zhang Shikun , Li Rui , Du Chunxiao , Xiao Zhisong 
Published: July 2024

Abstract
Variational quantum algorithms are considered one of the most promising methods for obtaining near-term quantum advantages; however, most of these algorithms are only expressed in the conventional quantum circuit scheme. The roadblock to developing quantum algorithms with the measurement-based quantum computation (MBQC) scheme is resource cost. Recently, we discovered that the realization of multi-qubit rotation operations only requires a constant number of single-qubit measurements with the MBQC scheme, providing a potential advantage in terms of resource cost. The structure of the Hamiltonian variational ansatz aligns well with this characteristic. Thus, we propose an efficient measurement-based quantum algorithm for quantum many-body system simulation tasks, called measurement-based Hamiltonian variational ansatz (MBHVA). We then demonstrate its effectiveness, efficiency, and advantages with the two-dimensional Heisenberg model and the Fermi–Hubbard chain. Numerical experiments show that MBHVA can have similar performance as circuit-based ansatz, and is expected to reduce operation counts during execution compared to quantum circuits, bringing the advantage of running time. We conclude that the MBQC scheme is potentially feasible for achieving near-term quantum advantages in the noisy intermediate-scale quantum era, especially in the presence of large multi-qubit rotation operations.
Multiphase cooperation for multilevel strain accommodation in a single-crystalline BiFeO3 thin film
Authors: Choi Wooseon , Park Bumsu , Hwang Jaejin , Han Gyeongtak , Yang Sang-Hyeok , Lee Hyeon Jun , Lee Sung Su , Jo Ji Young , Borisevich Albina Y. , Jeong Hu Young , Oh Sang Ho , Lee Jaekwang , Kim Young-Min 
Published: July 2024

Abstract
The functionalities and diverse metastable phases of multiferroic BiFeO3 (BFO) thin films depend on the misfit strain. Although mixed phase-induced strain relaxation in multiphase BFO thin films is well known, it is unclear whether a single-crystalline BFO thin film can accommodate misfit strain without the involvement of its polymorphs. Thus, understanding the strain relaxation behavior is key to elucidating the lattice strain–property relationship. In this study, a correlative strain analysis based on dark-field inline electron holography (DIH) and quantitative scanning transmission electron microscopy (STEM) was performed to reveal the structural mechanism for strain accommodation of a single-crystalline BFO thin film. The nanoscale DIH strain analysis results indicated a random combination of multiple strain states that acted as a primary strain relief, forming irregularly strained nanodomains. The STEM-based bond length measurement of the corresponding strained nanodomains revealed a unique strain accommodation behavior achieved by a statistical combination of multiple modes of distorted structures on the unit-cell scale. The globally integrated strain for each nanodomain was estimated to be close to −1.5%, irrespective of the nanoscale strain states, which was consistent with the fully strained BFO film on the SrTiO3 substrate. Density functional theory calculations suggested that strain accommodation by the combination of metastable phases was energetically favored compared to single-phase-mediated relaxation. This discovery allows a comprehensive understanding of strain accommodation behavior in ferroelectric oxide films, such as BFO, with various low-symmetry polymorphs.
Anisotropic pressure effect on central EOS of PSR J0740+6620 in the light of dimensionless TOV equation*
Authors: Yang 杨 Zhihao 致浩 , Wen 文 Dehua 德华 
Published: July 2024

Abstract
It is generally agreed upon that the pressure inside a neutron star is isotropic. However, a strong magnetic field or superfluidity suggests that the pressure anisotropy may be a more realistic model. We derived the dimensionless TOV equation for anisotropic neutron stars based on two popular models, namely, the BL and H models, to investigate the effect of anisotropy. Similar to the isotropic case, the maximum mass

and its corresponding radius

can also be expressed linearly by a combination of radial central pressure

and central energy density

, which is insensitive to the equation of state (EOS). We also found that the obtained central EOS would change with different values of

(

), which controls the magnitude of the difference between the transverse pressure and radial pressure. Combining with observational data of PSR J0740+6620 and comparing to the extracted EOS based on an isotropic neutron star, it is shown that in the BL model, for

= 0.4, the extracted central energy density

changed from 546 − 1056 MeV/fm3 to 510 − 1005 MeV/fm3, and the extracted radial central pressure

changed from 87 − 310 MeV/fm3 to 76 − 271 MeV/fm3. For

= 2, the extracted

and

changed to 412 − 822 MeV/fm3 and 50 − 165 MeV/fm3, respectively. In the H model, for

= 0.4, the extracted

changed to 626 − 1164 MeV/fm3, and the extracted

changed to 104 − 409 MeV/fm3. For

= 2, the extracted

decreased to 894 − 995 MeV/fm3, and the extracted

changed to 220 − 301 MeV/fm3.
Testing Bell inequality through
at CEPC*
Authors: Ma 马 Kai 凯 , Li 李 Tong 佟 
Published: July 2024

Abstract
The decay of Higgs boson into two spin-1/2 particles provides an ideal system to reveal quantum entanglement and Bell-nonlocality. Future

colliders can improve the measurement accuracy of the spin correlation of tau lepton pairs from Higgs boson decay. We show the testability of Bell inequality through

at Circular Electron Positron Collider (CEPC). Two realistic methods of testing Bell inequality are investigated, i.e., Törnqvist's method and Clauser-Home-Shimony-Holt (CHSH) inequality. In the simulation, we consider the detector effects of CEPC including uncertainties for tracks and jets from Z boson in the production of

. Necessary reconstruction approaches are described to measure quantum entanglement between

and

. Finally, we show the sensitivity of CEPC to Bell inequality violation for the two methods.
Chromomagnetic dipole moments of light quarks in the bestest little Higgs model
Authors: Cisneros-Pérez T. , Cruz-Albaro E. , Ojeda-Castañeda A. Y. , Solís-Núñez S. E. 
Published: July 2024

Abstract
In this study, we investigated the anomalous Chromomagnetic Dipole Moment (CMDM), denoted as

, of light quarks

within the framework of the Bestest Little Higgs Model (BLHM) as an extension of the Standard Model (SM). Our investigation encompassed novel interactions among the light quarks, heavy quark B, and heavy bosons

, incorporating the extended Cabibbo-Kobayashi-Maskawa (CKM) matrix characteristic of the BLHM. We thoroughly explored the permissible parameter space, yielding a spectrum of CMDM values ranging from

to

.
X-Ray Source Classification Using Machine Learning: A Study with EP-WXT Pathfinder LEIA
Authors: Zuo Xiaoxiong , Tao Yihan , Liu Yuan , Xu Yunfei , Zhang Wenda , Pan Haiwu , Sun Hui , Zhang Zhen , Cui Chenzhou , Yuan Weimin 
Published: July 2024

Abstract
X-ray observations play a crucial role in time-domain astronomy. The Einstein Probe (EP), a recently launched X-ray astronomical satellite, emerges as a forefront player in the field of time-domain astronomy and high-energy astrophysics. With a focus on systematic surveys in the soft X-ray band, EP aims to discover high-energy transients and monitor variable sources in the universe. To achieve these objectives, a quick and reliable classification of observed sources is essential. In this study, we developed a machine learning classifier for autonomous source classification using data from the EP-WXT Pathfinder—Lobster Eye Imager for Astronomy (LEIA) and EP-WXT simulations. The proposed Random Forest classifier, built on selected features derived from light curves, energy spectra, and location information, achieves an accuracy of approximately 95% on EP simulation data and 98% on LEIA observational data. The classifier is integrated into the LEIA data processing pipeline, serving as a tool for manual validation and rapid classification during observations. This paper presents an efficient method for the classification of X-ray sources based on single observations, along with implications of most effective features for the task. This work facilitates rapid source classification for the EP mission and also provides valuable insights into feature selection and classification techniques for enhancing the efficiency and accuracy of X-ray source classification that can be adapted to other X-ray telescope data.
The Unruh–DeWitt model and its joint interacting Hilbert space
Authors: Tjoa Erickson , Gray Finnian 
Published: July 2024

Abstract
In this work we make the connection between the Unruh–DeWitt (UDW) particle detector model applied to quantum field theory in curved spacetimes and the rigorous construction of the spin-boson (SB) model. With some modifications, we show that existing results about the existence of a SB ground state can be adapted to the UDW model. In the most relevant scenario involving massless scalar fields in (3+1)-dimensional globally hyperbolic spacetimes, where the UDW model describes a simplified model of light–matter interaction, we argue that common choices of the spacetime smearing functions regulate the ultraviolet behaviour of the model but can still exhibit infrared (IR) divergences. In particular, this implies the well-known expectation that the joint interacting Hilbert space of the model cannot be described by the tensor product of a two-dimensional complex Hilbert space and the Fock space of the vacuum representation. We discuss the conditions under which this problem does not arise and the relevance of the operator-algebraic approach for better understanding of particle detector models and their applications.Our work clarifies the connection between obstructions due to Haag’s theorem and IR bosons in the SB models, and paves the way for more rigorous study of entanglement and communication in the UDW framework involving multiple detectors.
Strongly quasi-mixing properties for one-dimensional diffusion processes with killing
*
Authors: Liao Saixia , Zhang Hanjun , Li Huasheng 
Published: July 2024

Abstract
In this paper, we establish sufficient conditions for the existence of strongly (uniformly and exponentially) quasi-mixing limits of one-dimensional diffusion processes with killing. As a by-product, these conditions also ensure that the considered processes have strong quasi-ergodicity, strong fractional quasi-ergodicity and uniform mean-ratio quasi-ergodicity. Moreover, the quasi-ergodic speeds of these three quasi-ergodicities are also characterized.
Five narrow bands terahertz metamaterial absorber based on metal and Dirac semi-metal for high sensitivity refractive index sensing
Authors: Liu Yulong , Xiao Zhongyin , Cai Xianshun , Zheng Qi 
Published: July 2024

Abstract
A five narrow bands terahertz metamaterial absorber based on metal and Dirac semi-metal for high sensitivity refractive index sensing is designed in this paper. The absorber is a traditional sandwich structure. And the most remarkable difference is that two hybrid materials (metal and Dirac semi-metal) are used in the top layer. The numerical results show five absorption peaks can be achieved at 5.527, 5.759, 7.247, 9.257 and 10.186 THz, among which the perfect absorption achieve at 5.759, 7.247 and 10.186 THz, respectively. The physical mechanism of the proposed absorber is analyzed qualitatively and quantitatively by electric field distributions and couple-mode theory. In addition, the sensing application of the proposed absorber is also studied. The sensitivity of the sensing band can reach up to 3.89 THz/RIU by computation. Finally, we design a specific application scenario to ensure the accuracy of the absorber in application through calculation. We believe that the absorber we designed will shine brilliantly in the fields of thermal imaging, thermal radiation and photothermal detection.