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Chinese Optics Letters 2024年第5期22卷 62-67页

作者：赵悦秦莹贾凯琳陈丽陈广伟胡国庆武腾飞李慧宇贺敬文周哲海 key laboratory of Modern Optoelectronic measurement technology in Mechanical Industry Beijing Information Science and Technology UniversityBeijing 100192China key laboratory of the Ministry of Education for Optoelectronic measurement technology and Instruments Beijing Information Science and Technology UniversityBeijing 100192China Changcheng Institute of Metrology&measurement Beijing 100095China National Physical Experiment Teaching Demonstration Center Beijing Jiaotong UniversityBeijing 100044China

We experimentally demonstrate tunable dual-comb soliton rains in a polarization multiplexing fiber laser based on a singlewalled carbon *** repetition frequency difference of dual-comb pulses is about 39 Hz,with a maximum extinction ratio of 29 *** suitable polarization states,one of the dual-comb pulses switches into soliton rain sequence with chirped isolating soliton *** signal-to-noise ratio reaches 61 dB,which is 11 dB higher than that of the normal dual-comb *** intervals between chirped isolating solitons are distributed progressively,and the number of isolating solitons can be flexibly tuned from 2 to 11 by adjusting polarization state or pump *** work will provide support for further understanding of interaction dynamics of solitons and give a new route to the application of precision measurement.

关键词： mode-locked fiber laser soliton rains dual-comb pulses gain relaxation dynamics single-walled carbon nanotube

Laser manufacturing of spatial resolution approaching quantum limit

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Light(Science & Applications) 2024年第3期13卷 421-428页

作者： Xiao-Jie Wang Hong-Hua Fang Zhen-Ze Li Dan Wang Hong-Bo Sun State key laboratory of Precision measurement technology and Instruments Department of Precision InstrumentTsinghua UniversityBeijing 100084China State key laboratory of Integrated optoelectronics College of Electronic Science and EngineeringJilin University2699 Qianjin StreetChangchun 130012China

Atomic and close-to-atom scale manufacturing is a promising avenue toward single-photon emitters,single-electron transistors,single-atom memory,and quantum-bit devices for future communication,computation,and sensing *** manufacturing is outstanding to this end for ease of beam manipulation,batch production,and no requirement for *** is,however,suffering from optical diffraction ***,we report a spatial resolution improved to the quantum limit by exploiting a threshold tracing and lock-in method,whereby the two-order gap between atomic point defect complexes and optical diffraction limit is surpassed,and a feature size of<5 nm is *** underlying physics is that the uncertainty of local atom thermal motion dominates electron excitation,rather than the power density slope of the incident *** show that the colour centre yield in hexagonal boron nitride is transformed from stochastic to deterministic,and the emission from individual sites becomes polychromatic to *** a result,single colour centres in the regular array are deterministically created with a unity yield and high positional accuracy,serving as a step forward for integrated quantum technological applications.

关键词： quantum limit resolution

Wearable Leg Movement Monitoring System for High-Precision Real-Time Metabolic Energy Estimation and Motion Recognition

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Research 2024年第2期2023卷 417-429页

作者： Jinfeng Yuan Yuzhong Zhang Shiqiang Liu Rong Zhu State key laboratory of Precision measurement technology and Instruments Department of Precision InstrumentTsinghua UniversityBeijing 100084China

Comprehensive and quantitative assessment of human physical activity in daily life is valuable for healthcare,especially for those who suffer from obesity and neurological disorders or are at high risk of *** wearable devices,e.g.,smartwatches,are insufficient and inaccurate for monitoring highly dynamic limb movements and assessing human ***,we report a new wearable leg movement monitoring system incorporating a custom-made motion sensor with machine learning algorithm to perceive human motion accurately and comprehensively during diverse walking and running *** system enables real-time multimodal perceptions of personal identity,motion state,locomotion speed,and energy expenditure for wearers.A general law of extracting real-time metabolic energy from leg movements is verified although individual gaits show *** addition,we propose a novel sensing configuration combining unilateral lower leg movement velocity with its angular rate to achieve high accuracy and good generalizability while simplifying the wearable *** performances in personal identification(accuracy of 98.7%)and motion-state recognition(accuracy of 93.7%)are *** wearable system also exhibites high-precision real-time estimations of locomotion speed(error of 3.04%to 9.68%)and metabolic energy(error of 4.18%to 14.71%)for new subjects across various time-varying *** wearable system allows reliable leg movement monitoring and quantitative assessment of bodily kinematic and kinetic behaviors during daily activities,as well as safe identity authentication by gait parameters,which would greatly facilitate smart life,personal healthcare,and rehabilitation training.

关键词： smart enable monitoring

Electrostatic generator enhancements for powering IoT nodes via efficient energy management

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Microsystems & Nanoengineering 2024年第2期10卷 143-152页

作者： Zibo Wu Zeyuan Cao Junchi Teng Rong Ding Jiani Xu Xiongying Ye State key laboratory of Precision measurement technology and Instruments Department of Precision InstrumentTsinghua University100084BeijingChina

Electrostatic generators show great potential for powering widely distributed electronic devices in Internet of Things(IoT)***,a critical issue limiting such generators is their high impedance mismatch when coupled to electronics,which results in very low energy utilization ***,we present a high-performance energy management unit(EMU)based on a spark-switch tube and a buck converter with an RF *** optimizing the elements and parameters of the EMU,a maximum direct current output power of 79.2 mW m^(-2)rps^(-1)was reached for a rotary electret generator with the EMU,achieving 1.2 times greater power output than without the ***,the maximum power of the contact-separated triboelectric nanogenerator with an EMU is 1.5 times that without the *** excellent performance is attributed to the various optimizations,including utilizing an ultralow-loss spark-switch tube with a proper breakdown voltage,adding a matched input capacitor to enhance available charge,and incorporating an RF inductor to facilitate the high-speed energy transfer *** on this extremely efficient EMU,a compact self-powered wireless temperature sensor node was demonstrated to acquire and transmit data every 3.5 s under a slight wind speed of 0.5 m/*** work greatly promotes the utilization of electrostatic nanogenerators in practical applications,particularly in IoT nodes.

关键词： IoT power generator

Metasurface array for single-shot spectroscopic ellipsometry

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Light(Science & Applications) 2024年第5期13卷 835-842页

作者： Shun Wen Xinyuan Xue Shuai Wang Yibo Ni Liqun Sun Yuanmu Yang Department of Precision Instrument State Key Laboratory of Precision Measurement Technology and InstrumentsTsinghua UniversityBeijing 100084China

Spectroscopic ellipsometry is a potent method that is widely adopted for the measurement of thin film thickness and refractive *** conventional ellipsometers utilize mechanically rotating polarizers and grating-based spectrometers for spectropolarimetric ***,we demonstrated a compact metasurface array-based spectroscopic ellipsometry system that allows single-shot spectropolarimetric detection and accurate determination of thin film properties without any mechanical *** silicon-based metasurface array with a highly anisotropic and diverse spectral response is combined with iterative optimization to reconstruct the full Stokes polarization spectrum of the light reflected by the thin film with high ***,the film thickness and refractive index can be determined by fitting the measurement results to a proper material model with high *** approach opens up a new pathway towards a compact and robust spectroscopic ellipsometry system for the high throughput measurement of thin film properties.

关键词： properties. spectroscopic film

Voltage-modulated polymer nanopore field-effect transistor for multi-sized nanoparticle detection

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Nanotechnology and Precision Engineering 2024年第3期7卷 79-89页

作者： Feng Zhou Lin Li Qiannan Xue State key laboratory of Precision measurement technology and Instruments School of Precision Instruments and Optoelectronics EngineeringTianjin UniversityTianjin 300072China

Solid-state nanopores offer a range of distinct advantages over biological nanopores,such as structural diversity and greater stability and durability;this makes them highly promising for high-resolution nanoparticle *** nanopores can exhibit gating characteristics with stress-responsive switches and can demonstrate specificity toward particular *** inspiration from biological nanopores,this paper introduces a novel polymer nanopore with field-effect characteristics,leveraging a conductive polymer in its construction to showcase intriguing gating ***,in this device,the polymer layer serves as the gate,enabling precise control over the source–drain current response inside and outside the pore by simply adjusting the gate *** unique feature allows fine-tuning of the nanopore’s sensitivity to nanoparticles of varying sizes and facilitates its operation in multiple *** results reveal that the developed polymer nanopore field-effect transistor demonstrates remarkable selectivity in detecting nanoparticles of various sizes under different applied *** proposed single device demonstrates the exceptional ability to detect multiple types of nanoparticle,showcasing its immense potential for a wide range of applications in biological-particle analysis and medical diagnostics.

关键词： Nanopipette Polymer nanopore Voltage modulation Nanoparticle detection

Spatial light modulation for femtosecond laser manufacturing:Current developments and challenges

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Science China(Technological Sciences) 2024年第1期67卷 60-72页

作者： ZANG Xue LIU ZiTing XU YiShi WANG Yi WANG Qing LI ZhenZe WANG Lei State key laboratory of Integrated optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012China State key laboratory of Precision measurement and Instruments Department of Precision InstrumentTsinghua UniversityBeijing 100084China

Since the invention of lasers,spatial-light-modulated laser processing has become a powerful tool for various *** enables multidimensional and dynamic modulation of the laser beam,which significantly improves the processing efficiency,accuracy,and flexibility,and presents wider prospects over traditional mechanical technologies for machining three-dimensional,hard,brittle,or transparent *** this review,we introduce:(1)The role of spatial light modulation technology in the development of femtosecond laser manufacturing;(2)the structured light generated by spatial light modulation and its generation methods;and(3)representative applications of spatial-light-modulated femtosecond laser manufacturing,including aberration correction,parallel processing,focal field engineering,and polarization ***,we summarize the present challenges in the field and possible future research.

关键词： femtosecond laser manufacturing spatial light modulation structured light aberration correction parallel processing focal field engineering polarization control

A semantic vector map-based approach for aircraft positioning in GNSS/GPS denied large-scale environment

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Defence technology（防务技术） 2024年第4期34卷 1-10页

作者： Chenguang Ouyang Suxing Hu Fengqi Long Shuai Shi Zhichao Yu Kaichun Zhao Zheng You Junyin Pi Bowen Xing State key laboratory of Precision measurement technology and Instruments Tsinghua UniversityBeijing 100084China School of Mechanical and Information Engineering China University of Mining and Technology(Beijing)Beijing 100083China

Accurate positioning is one of the essential requirements for numerous applications of remote sensing data,especially in the event of a noisy or unreliable satellite *** this end,we present a novel framework for aircraft geo-localization in a large range that only requires a downward-facing monocular camera,an altimeter,a compass,and an open-source Vector Map(VMAP).The algorithm combines the matching and particle filter *** vector and correlation between two building contour vectors are defined,and a coarse-to-fine building vector matching(CFBVM)method is proposed in the matching stage,for which the original matching results are described by the Gaussian mixture model(GMM).Subsequently,an improved resampling strategy is designed to reduce computing expenses with a huge number of initial particles,and a credibility indicator is designed to avoid location mistakes in the particle filter *** experimental evaluation of the approach based on flight data is *** a flight at a height of 0.2 km over a flight distance of 2 km,the aircraft is geo-localized in a reference map of 11,025 km~2using 0.09 km~2aerial images without any prior *** absolute localization error is less than 10 m.

关键词： Large-scale positioning Building vector matching Improved particle filter GPS-Denied Vector map

Gate-field control of valley polarization in valleytronics

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Chinese Physics B 2024年第6期33卷 2-12页

作者：张婷婷韩依琳张闰午余智明 Institute of Physics Chinese Academy of SciencesBeijing 100190China key laboratory of Advanced Optoelectronic Quantum Architecture and measurement Beijing Key Laboratory of Nanophotonics&Ultrafine Optoelectronic Systemsand School of PhysicsBeijing Institute of TechnologyBeijing 100081China

Valleytronics materials are a kind of special semiconductors which can host multiple symmetry-connected and wellseparated electron or hole pockets in the Brillouin zone when the system is slightly n or p doped. Since the low-energy particles residing in these pockets generally are not easily scattered to each other by small perturbations, they are endowed with an additional valley degree of freedom. Analogous to spin, the valley freedom can be used to process information,leading to the concept of valleytronics. The prerequisite for valleytronics is the generation of valley polarization. Thus,a focus in this field is achieving the electric generation of valley polarization, especially the static generation by the gate electric field alone. In this work, we briefly review the latest progress in this research direction, focusing on the concepts of the couplings between valley and layer, i.e., the valley–layer coupling which permits the gate-field control of the valley polarization, the couplings between valley, layer, and spin in magnetic systems, the physical properties, the novel designing schemes for electronic devices, and the material realizations of the gate-controlled valleytronics materials.

关键词： band structure electronic transport optical properties spintronics

Reconfigurable logic and in-sensor encryption operations in an asymmetrically tunable van der Waals heterostructure

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Nano Research 2024年第4期17卷 3113-3119页

作者： Fan Gong Wenjie Deng Yi Wu Fengming Liu Yihao Guo Zelin Che Jingjie Li Jingzhen Li Yang Chai Yongzhe Zhang key laboratory of optoelectronics technology of Education Ministry of China Faculty of Information TechnologyBeijing University of TechnologyBeijing 100124China key laboratory of Advanced Functional Materials Ministry of EducationFaculty of Materials and ManufacturingBeijing University of TechnologyBeijing 100124China Department of Applied Physics Hong Kong Polytechnic UniversityKowloonHong KongChina

Reconfigurable devices can be used to achieve multiple logic operation and intelligent optical sensing with low power consumption,which is promising candidates for new generation electronic and optoelectronic integrated ***,the versatility is still limited and need to be extended by the device architectures ***,we report an asymmetrically gate two-dimensional(2D)van der Waals heterostructure with hybrid dielectric layer SiO_(2)/hexagonal boron nitride(h-BN),which enable rich function including reconfigurable logic operation and in-sensor information encryption enabled by both volatile and non-volatile optoelectrical *** the partial gate is grounded,the non-volatile light assisted electrostatic doping endowed partially reconfigurable doping between n-type and p-type,which allow the switching of logic XOR and not implication(NIMP).When the global gate is grounded,additionally taking the optical signal as another input signal,logic AND and OR is realized by combined regulation of the light and localized gate *** on the high on/off current ratio approaching 105 and reliable&switchable logic gate,in-sensor information encryption and decryption is demonstrated by manipulating the logic ***,these results provide strong extension for current reconfigurable electronic and optoelectronic devices.

关键词： in-sensor encryption reconfigurable logic van der Waals heterostructure asymmetrical tunable architecture