bluuebunny/crossref_metadata_2025_split huggingface dataset:
Long-wave infrared laser irradiation damage effect on GaAs/AlGaAs quantum well infrared photodetector
Authors: Sun Jiaxin , Qian Chuanpeng , Liu Xiaolin , Xu Zuodong , Zhang Yan , Li Xiangyang , Lu Wei , Zhang Jianmin , Ye Xisheng 
Published: April 2024

Abstract
The damage effect and mechanism of laser irradiation on long-wave focal plane array (FPA) GaAs/AlGaAs quantum well infrared photodetector (QWIP) were preliminarily explored by using numerical simulation and experiment methods. Piecewise functions were employed to simulate the complex boundary structure of the QWIP, enabling the numerical simulation investigation of mono-pulse, nano-second, long-wave infrared laser irradiation damage effect on the QWIP. The highest QWIP temperature, the highest surface temperature and the maximum circumferential thermal stress were analyzed in relation to laser energy density. The pulse average energy density thresholds of thermal decomposition damage, melting damage and thermal stress-induced damage were theoretically obtained. Preliminary experiments were then conducted by using a mono-pulse, nano-second, 7.2 μm all-solid-state long-wave infrared laser. The experimental results revealed a point-shape damage in QWIP response measurement after the irradiation by a laser pulse of average energy density 1.30 J cm−2, due to the decomposition of GaAs. At a higher average energy density 5.42 J cm−2, both melting and stress-induced damages appeared, with the damage morphology predominantly influenced by stress-induced damage, resulting in the occurrence of blind pixels or the losing of pixels. Furthermore, at laser pulse average energy density 12.48 J cm−2, line-shape damage of the QWIP was observed.
Terahertz generation of Airy beam with polarization conversion in a reflective vanadium dioxide metasurface
Authors: Zhou Zhesheng , Zhang Runxuan , Chen Zijun , Nie Ruixing , Pan Zimo , Song Zhengyong 
Published: April 2024

Abstract
Airy beam possesses a wide range of applications owing to its special properties of non-diffraction, self-accelerating, and self-healing. However, conventional Airy beam generators are not conducive to their miniaturization or integration. In this paper, a technique for generating Airy beam is introduced with polarization conversion within the frequency range of 0.9–1.2 THz based on a reflective vanadium dioxide (VO2) metasurface. Our design is composed of VO2 elliptical patch, SiO2 spacer, and gold substrate. When the metallic VO2 is involved, the proposed metasurface can efficiently generate cross-polarized Airy beam since amplitude and phase distributions of reflected wave are modulated simultaneously by rotating tilt angle of each VO2 patch. Conversely, when the insulating VO2 is involved, the metasurface does not generate Airy beam. In addition, we demonstrate broadband effect and autofocusing phenomenon of the metasurface. The proposed Airy beam generator may be of great interest for beam shaping, biomedical imaging, and laser fabrication.
Stable stripe and vortex solitons in two-dimensional spin-orbit coupled Bose–Einstein condensates
Authors: Guo Yuan , Idrees Muhammad , Lin Ji , Li Hui-jun 
Published: April 2024

Abstract
We present a flexible manipulation and control of solitons via Bose–Einstein condensates. In the presence of Rashba spin–orbit coupling and repulsive interactions within a harmonic potential, our investigation reveals the numerical local solutions within the system. By manipulating the strength of repulsive interactions and adjusting spin–orbit coupling while maintaining a zero-frequency rotation, diverse soliton structures emerge within the system. These include plane-wave solitons, two distinct types of stripe solitons, and odd petal solitons with both single and double layers. The stability of these solitons is intricately dependent on the varying strength of spin–orbit coupling. Specifically, stripe solitons can maintain a stable existence within regions characterized by enhanced spin–orbit coupling while petal solitons are unable to sustain a stable existence under similar conditions. When rotational frequency is introduced to the system, solitons undergo a transition from stripe solitons to a vortex array characterized by a sustained rotation. The rotational directions of clockwise and counterclockwise are non-equivalent owing to spin–orbit coupling. As a result, the properties of vortex solitons exhibit significant variation and are capable of maintaining a stable existence in the presence of repulsive interactions.
Destabilization of geodesic acoustic-like mode in the presence of poloidally inhomogeneous heat sources in tokamak plasmas
Authors: Lee Young-Hoon , Lee Jungpyo 
Published: April 2024

Abstract
The effects of poloidally inhomogeneous heat sources are investigated through a gyrokinetic formula in collisionless toroidal plasmas. A gyrokinetic dispersion relation is newly derived under the assumption that equilibrium parallel heat flows are generated to remove the injected poloidally nonuniform heat source. The dispersion relation is numerically solved, considering both inboard and outboard heat source injections. In the case of the inboard source injection, both Stringer spin-up and geodesic acoustic mode (GAM) are excited. Conversely, outboard injection leads to the emergence of a heat source-driven GAM (referred to as Q-GAM), featuring a frequency around half that of the standard GAM. Various physical quantities of the Q-GAM, such as mode frequency and source threshold, are analyzed through parametric scans. The Q-GAM exhibits similarities with the energetic-particle-driven GAM (EGAM), particularly in its frequency range, and both belong to one of the strong Landau damped poles. Despite having distinct driving mechanisms and structural differences in parallel velocity and poloidal coordinates, the response function of the perturbed parallel pressure to the potential, mainly contributing to the destabilization of each mode around half of the GAM frequency, is derived to have a similar form for both the Q-GAM and EGAM cases.
Size effect on vibration properties of axially moving nanoplates under different boundary conditions
Authors: Jing Wang , Yanglan Yu 
Published: April 2024

Abstract
The nonlocal strain gradient theory is employed to investigate the transverse free vibration characteristics of two-dimensional nano-plates with axial velocities. A generalized Hamiltonian principle has been used to establish the vibration governing equations for the system as well as the corresponding boundary conditions. By applying complex modal analysis to three boundary conditions, the plate’s natural frequency is determined, including four-end simply supported, four-end clamped, and opposite-edge simply supported and clamped, and comparing the effect of the size parameters on the natural frequency in relation to the boundary conditions; based on different theories, the effects of changing boundary conditions on natural frequencies are systematically compared. In the numerical study, it is demonstrated that the size effect significantly influences only the self-oscillation frequency at the nanoscale, whereas the nonlocal parameter as well as the material characteristic parameter have “softening” and “hardening” effects on the equivalent stiffness of the nanoplates, respectively, which are directly related to their natural frequencies. Compared to simple supports, clamped boundary conditions are more significantly affected by size parameters. In addition, higher order frequencies exhibit greater sensitivity and are susceptible to changes in boundary conditions and size parameters.
ScxAl1-xN piezoelectric film grown at room temperature
Authors: Liu Jingyan , Ma Liang , Ma Yaming , Yang Shuqiang , Chen Yuxin , Zeng Seng , Shang Zhengguo , He Xianming , Wang Hongli 
Published: April 2024

Abstract
In order to overcome the shortcomings of AlN piezoelectric thin films such as low piezoelectric coefficient and low electromechanical coupling coefficientrealize, ScxAl1−xN thin films with CMOS process compatibility were prepared by pulsed DC reactive magnetron sputtering. High performance ScxAl1−xN piezoelectric thin films were prepared at room temperature by optimizing process parameters including power, gas flow ratio, substrate temperature, seed layers and so on. The phase separation phenomenon was investigated through XRD, TEM, and XPS. We found that the phase separation is related to the appearance of rocksalt ScN and led to the degeneration of film properties. The existence of ScN phase is a key factor affecting the performance of ScxAl1−xN. The results show that the piezoelectric constant d33 of ScAlN film achieved 27.5 pC/N and the full width at half maximum (FWHM) of the rocking curve is 1.9° in room temperature when the content of Sc reaches 35%.
A novel sensible smart mask using micro thermal-electric energy conversion elements
Authors: Zhang Yun , Ren Xiaoming , Gou Yanjie , Shen Qingke 
Published: April 2024

Abstract
With the improvement of people’s living standards, more and more people begin to pay attention to their own health status. The mode of monitoring human physiological indicators is gradually shifting to a family-based and miniaturized development model that focuses on prevention. Respiratory rate is an important parameter that reflects the health status of the human body. It is an important diagnostic basis for doctors in clinical prevention and diagnosis of related diseases. Therefore, it is necessary to develop a portable monitoring instrument that can dynamically monitor the human respiratory frequency index in real time. Since most of the existing wearable respiratory frequency detection devices have some disadvantages such as low accuracy, high cost and difficulty in promotion, this paper proposes a new type of smart mask based on thermoelectric effect to monitor human respiratory frequency in real time. The respirator system has the advantages of small size, light weight and suitable for face. Compared with other heavy breathing devices, it has obvious advantages. The Seebeck effect of thermoelectric energy conversion element (TECE) can be used to reflect the respiratory frequency of human body under different respiratory conditions. Experiments show that the sensor has high accuracy and can accurately reflect even small changes in respiratory frequency.
Advancing simulation efficiency for MEMS electrostatic actuators
Authors: Wang Lei , Liu Haiyun , Liu Xing 
Published: April 2024

Abstract
This paper presents an overview of the research progress on Multiphysics simulation of MEMS electrostatic actuators. MEMS electrostatic actuators have shown significant development potential in applications such as ADWSS and VOA. However, the increasing size and complexity of these devices have posed challenges to traditional Multiphysics simulation methods, leading to lengthy computational times that hinder the overall device development process. In order to enhance simulation efficiency and meet the demands of device development, the use of simplified single physics field models have been explored. The results have demonstrated that the simplified single physics filed simulation model yields comparable results to traditional Multiphysics simulations with an error tolerance of within 10%, while reducing simulation time by 80-90%.
A sensor system integrating sensing and intelligence based on MEMS reservoir computing
Authors: Guo Xiaowei , Yang Wuhao , Zou Xudong 
Published: April 2024

Abstract
Reservoir computing (RC) is a bio-inspired neural network structure which is easy to be implemented in hardware. It has been constructed in a great many fields such as memristor, electrochemical reaction, among which MEMS is the closest to integrate sensing and computing. We propose a novel sensor system of MEMS RC based on stiffness modulation, that natural signal directly affects the system stiffness as the input. Under this paradigm, information can be processed locally without data collection and pre-processing. We inherited the nonlinearity tuning principle and optimized the post-processing algorithm by creating a digital mask operator. In this way, the system can deal with classification tasks as well as forecasting tasks. We integrated MEMS, IC and FPGA with a small volume and low power consumption, so complicated setup for data discretization and transduction in traditional MEMS RC is eliminated. The system can process word classification and chaos forecasting with high accuracy, which preliminarily proves the integrated RC architecture.
Mixed metal differentiation method using microfluidic oil detection sensors
Authors: Xie Yucai , Shi Haotian , Zhang Hongpeng 
Published: April 2024

Abstract
This paper analyzes the characteristics of iron particles and copper particles in the alternating magnetic field with the change of excitation frequency, and proposes a method of using microfluidic oil detection sensor to achieve the distinction of mixed metals. The magnetic field strength of the coil is changed by changing the excitation frequency, which in turn makes the metal particles of different materials act with different strengths in the magnetic field, and realizes the accurate detection of the particles. In the article, firstly, the magnetization effect of the particles in the alternating magnetic field is simulated by the simulation software, the change of the magnetization effect with frequency is simulated, and the change curve of the inductance signal when the particles pass is obtained. Then the experimental verification is carried out by building a test bench, and the experimental results are consistent with the simulation results, which all confirm the feasibility of realizing the detection of aliased particles by frequency conversion. The method provides a new reference direction for the precise and accurate detection of oil detection technology, and has good research value.
Optical force on yeast cells generated from surface plasmon polaritons
Authors: Zhao Hangxin , Song Xinyu , Han Xue 
Published: April 2024

Abstract
The surface plasmon resonance phenomenon is widely used in sensing, near-field control, and nonlinear optics. In this paper, the optical near-field generated by the surface plasmon resonance phenomenon is applied to trap yeast cells. The effect of the relative axial distance between the gold film surface and the waist of the focused beam on the trap stiffness is studied. There is a maximized trap stiffness at a specific relative axial distance for trapping yeast cells. The trap stiffness is significantly higher than the value at other locations. This study can be applied to screening of particles with different sizes.
Low stress packaging of the small three-axis gyro
Authors: Yunjie Yang , Yunkang Song , Xin Yan , Gang Wang , Huaxiang Yi , Zhengnan Zhang , Jiang Rao 
Published: April 2024

Abstract
High-precision combined three-axis MEMS gyroscope is popular because of its high integration and miniaturization, but it also puts forward higher requirements for packaging. In this paper, the designed stress isolation structure is bonded between the MEMS chip and the package substrate according to the low stress method, which said the external stress is blocked and offset by the reverse stress generated by the elastic beam in the stress isolation structure, so as to ensure that the MEMS chip is kept in a low stress state. Simulation results show that the stress isolation structure can block 93.3% of the stress transmitted by the outside world. In the actual test, the stress isolation structure can also ensure that the output of the single-axis module of the three-axis gyro is stable and reliable, so as to improve the survival rate of the product.
FPGA-based interference elimination for health monitoring in dynamic environments
Authors: Jiang Jiaxin , Pan Yijing , Wang Xiang , Li Shufan , Zhang Runyang , Liu Yifang , Zheng Gaofeng , Zhuo Liyun , Li Wenwang 
Published: April 2024

Abstract
Since flexible wearable sensing devices are mostly used to acquire the human health information by fitting, the vibration generated by the wearer’s movement, physiological state, environment, and other dynamic factors will interfere the accuracy of collected signals. In order to solve the signal interference problem in dynamic environments, a system is needed to eliminate the strong interfering signals in disturbing scenarios in order to acquire the target signal. In this paper, a FPGA-based system is designed to eliminate the signal interference, where a PFGA chipset is served as the core hardware part, an adaptive notch filter is used to process the sensing signals and the FPGA and the host computer are interacted in real time, thus various vibration noises suffered by the flexible sensing device could be eliminated when it is applied to health monitoring in dynamic environments.
A frequency meter based on Costas FLL for resonant accelerometers
Authors: Yafei Xie , Rui Feng , Liuhui Zhou , Jiazhan Fu , Yahui Su , Ming Zhou 
Published: April 2024

Abstract
The resonant accelerometer (RA) is an important part for high-performance inertial devices. And high accuracy frequency measurement is one of the key technology for RA. This paper developed a frequency meter based on Costas frequency lock loop (FLL). This structure is flexible as the analog input sinusodial voltage wave is converted into digital domain by an ADC and the frequency measurement function dealing with that voltage could be implemented only with digital circuits. The transfer function of the frequency meter is determined by the loop filter of the FLL and the closed system is always stable for PID controller. The noise in the loop is reshaped by a first order ∑-Δ modulator formed by the frequency meter loop, which relaxes the requirement for the accuracy of ADC. A test board for the frequency meter is implemented with a 24-bit ADC and FPGA, and achieves a noise of

1

mHz
/

Hz

at low frequency band,

7

µ
Hz
/

Hz

around 50 Hz with a 40 kHz sinusodial input voltage.
Heterogeneous Integration for High Performance Electronic and Photonic Devices
Authors: Dai Jiayun , Wang Fei , Li Guanyu , Jia Chenyang , Ling Zhijian , Chen Xin , Kong Yuechan , Chen Tangsheng 
Published: April 2024

Abstract
In this paper, two representative heterogeneous integrated applications with great performance based on epitaxial layer transfer process are reported. The SiC integrated Si PIN limiter has shown power handling capability of 150W (continues Wave) and 370W (long pulse) at 5.4GHz, which shows outstanding performance than conventional GaAs limiter. While the SiC integrated InP PIN photodetector has shown a high performance of 3-dB bandwidth over 67GHz, and 42% increasing of the optical responsibility over 0.51 A/W compared to the traditional PD. The results verified great potential of transistor level heterogeneous integration for high performance electronic and photonic devices.
Fabrication and application of flexible piezoelectric sensor based on electrospun PVDF-TrFE nanofibers
Authors: Li Wenwang , Xie Angda , Jiang Jiaxin , Zheng Gaofeng , Li Shufan , Zhang Runyang , Wang Xiang 
Published: April 2024

Abstract
Flexible piezoelectric sensors have recently demonstrated great promise for use in wearable electronics and electronic skin. In this study, electrospinning was used to generate piezoelectric PVDF-TrFE nanofiber sensors. The relationship between nanofiber alignment orientation and piezoelectric property was examined. The experimental results demonstrated that the piezoelectric property improved with the increasing of nanofiber alignment orientation. The response time of piezoelectric sensor was 2 ms, and the sensitivity was 0.446 V/N and 0.029 V/N at vibration frequency of 5 Hz and 1 Hz, respectively. In addition, the applications of flexible piezoelectric sensor in human joint movements and surface contact have been demonstrated, indicates the potential in the field of motion monitoring.
Design of a PWM/PFM hybrid modulation switching circuit for a four-switch buck-boost converter
Authors: Song N. , Fang S. , Zhao C. , Wang Y. 
Published: April 2024

Abstract
Based on the application background of fuel cell, the conversion efficiency of the four-switch Buck-Boost converter using PWM (Pulse width modulation) is low at light load, and the conversion efficiency of the four-switch Buck-Boost converter using PFM (Pulse frequency modulation) is low at heavy load. A PWM/PFM hybrid modulation circuit using digital module to detect induced current and feedback voltage is presented. The circuit structure is simple and easy to integrate. It has the effect of fast selection according to inductance current and feedback voltage. The circuit works in PWM mode by default. After soft startup, PWM/PFM mode can be switched according to the load. Finally, simulation is carried out in FSBB converter. The experimental results show that the PWM/PFM hybrid modulation circuit has the function of multi-load lead switching mode and protection mechanism. Simulation in FSBB converter shows that the converter efficiency reaches 91.99% and the maximum load current is 2A. This helps improve the efficiency of Buck-Boost converters.
Equipment develop and experiment study of the synchronization of electrospinning and electrospray
Authors: Wang Xiang , Shi Haochen , Pan Zaibin , Jiang Jiaxin , Li Shufan , Zhang Runyang , Liao Wenhai , Zheng Gaofeng , Li Wenwang 
Published: April 2024

Abstract
High-performance multi-functional nanomaterials have broad applications in various industrial fields. The assembling of nanofibers and nanoparticles prepared by electrospinning and electrospray is a typical structure for the functional combination of multi-materials. However, due to different solution properties and processing parameters, as well as the simultaneous mutual interferences, the controlling of the synchronization of electrospinning and electrospray technology is in an urgent demand. In this paper, an equipment was developed to realize the synchronization of electrospinning and electrospray technology, and multi-functional nanomaterials combining nanofibers and nanoparticles was achieved. Then, thermoplastic polyurethanes (TPU)/grapheneoxide (GO) and poly(lactic acid) PLA/polyaniline (PANI) membrane was prepared based on the self-developed equipment, verifying the process of the synchronization of electrospinning and electrospray.
Circuit design of a novel front readout circuit for SiC neutron detector with leakage current compensation
Authors: Liu J. , Liu Y. , Fang S. , Liu X. , Wang Y. 
Published: April 2024

Abstract
Radiation detectors have broad application prospects in environmental radiation monitoring, radiation source identification, biomedical imaging, space exploration, astrophysics, other radiation detection and imaging fields. Among the third generation semiconductors, the properties of 4H-SiC are more suitable for making high-temperature and strong radiation neutron detectors. SiC materials have become a current research hotspot. In this paper a special readout integrated circuit is designed for the extremely weak current pulse signal output by SiC trench neutron detector. A leakage current compensation circuit is designed for the influence of leakage current on charge sensitive amplifier(CSA) output baseline. The noise of CSA output is analyzed and the noise minimization is carried out. The circuit can quickly respond to the input signal and extract the energy and time information. The circuit is designed based on the DB Hitek 0.18μm CMOS process model. The layout design is achieved and the post-simulation is completed. Simulated results show that the equivalent input charge range of the system is about 2fC ∼ 20fC. The charge conversion gain is 88mV/fC. The nonlinear error is within 1.6 %. Moreover, the equivalent noise charge is 22e-. The circuit has the advantages of high gain, high linearity and low noise. Therefore, the circuit can effectively adapt to the characteristics of the charge signal output from SiC trench neutron detectors and amplify the output charge signal.