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Power output correction model of narrow linewidth ring fiber laser filtered with whispering gallery mode resonator

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Chinese Optics Letters 2024年第3期22卷 60-64页

作者：王子云徐在斌崔继文谭久彬 Center of ultra-precision Optoelectronic Instrument Harbin Institute of TechnologyHarbin 150080China key laboratory of ultra-precision intelligent instrumentation Ministry of Industry and Information TechnologyHarbin Institute of TechnologyHarbin 150080China

A whispering gallery mode resonator(WGMR)filter can narrow laser linewidth while significantly changing the output power characteristics of fiber laser system.It is found that traditional laser output power model is invalid.We report a correction model of a narrow linewidth fiber laser filtered with a WGMR to analyze its power.We believe that the loss of the laser system and the threshold gain increase caused by the WGMR filter lead to the predominate amplified spontaneous emission during the original laser period.According to that,we assume the correction coefficient is an exponential decay related to the Er-doped fiber length in the large loss situation,and we verify it experimentally.As a result,the correction model is valid for WGMR-filtered fiber laser.

关键词： whispering gallery resonator filter narrow linewidth fiber laser power output correction model

Design of a high frequency accuracy heterodyne laser source working in a wide temperature range

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Chinese Optics Letters 2024年第4期22卷 83-88页

作者：杨宏兴王彦殷子淇胡鹏程杨睿韬李婧 Center of ultra-precision Optoelectronic Instrument Harbin Institute of TechnologyHarbin 150080China key laboratory of ultra-precision intelligent instrumentation(Harbin Institute of Technology) Ministry of Industry and Information TechnologyHarbin 150080China

To ensure the frequency accuracy of a heterodyne laser source in the ambient temperature range of-20℃ to 40℃, a duallongitudinal-mode thermally stabilized He–Ne laser based on non-equilibrium power locking was designed. The ambient adaptive preheating temperature setting scheme ensured the laser could operate normally in the range of-20℃ to40℃. The non-equilibrium power-locked frequency stabilization scheme compensated for the frequency drift caused by different stabilization temperatures. The experimental results indicated that the frequency accuracy of the laser designed in this study could reach 5.2 × 10^(-9)in the range of-20℃ to 40℃.

关键词： He–Ne laser frequency accuracy ambient adaptability non-equilibrium power locking

Vibration harmonic suppression technology for electromagnetic vibrators based on an improved sensorless feedback control method

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Frontiers of Information Technology & Electronic Engineering 2024年第3期25卷 472-483页

作者： Wei LI Junning CUI Xingyuan BIAN Limin ZOU Centerof ultra-precision Optoelectronic Instrument Engineering Harbin Institute of TechnoogyHarbin 0080China key Lab of ultra-precision Intlligent instrumentation(Harbin Institute of Technology).Ministry of Industry and Information Technology Harbin 150080China

To realize low harmonic distortion of the vibration waveform output from electromagnetic vibrators,we propose a vibration harmonic suppression technology based on an improved sensorless feedback control method.Without changing the original driving circuit,the alternating current(AC)equivalent resistance of the driving coil is used to obtain high-precision vibration velocity information,and then a simple and reliable velocity feedback control system is established.Through the study of the effect of different values of key parameters on the system,we have achieved an effective expansion of the velocity characteristic frequency band of low-frequency vibration,resulting in an enhanced harmonic suppression capability of velocity feedback control.We present extensive experiments to prove the effectiveness of the proposed method and make comparisons with conventional control methods.In the frequency range of 0.01-1.00 Hz,without using any sensors,the method proposed in this study can reduce the harmonic distortion of the vibration waveform by about 40%compared to open-loop control and by about 20%compared to a conventional sensorless feedback control method.

关键词： Vibration calibration Electromagnetic vibrators Harmonic suppression Sensorless control method Velocity feedback control

Design and identification of a double-acting piezoelectric-hydraulic hybrid actuator

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Chinese Journal of Aeronautics 2024年第3期37卷 456-467页

作者： Junjian ZHANG Zhihua FENG key laboratory of precision Scientific instrumentation of Anhui Higher Education Institutes University of Science and Technology of ChinaHefei 230026China

Traditional single-acting piezoelectric-hydraulic hybrid actuators usually have the problem of inertial force caused by flow pulsation of the liquid,which degrades their output performance.To suppress or solve the associated inertial force and enhance its output capabilities,this paper proposes a new type of double-acting piezoelectric-hydraulic hybrid actuator with four check valves acting as mechanical diodes.The new hybrid actuator was fabricated and its output performance was tested.When the voltage is 700 Vp-pand the bias pressure is 2 MPa,the pulsation ratesδof the new actuator at 400 Hz,500 Hz and 600 Hz are 2.29,2.08 and 1.78,respectively,whileδof the single-acting hybrid actuator under the same conditions are 10.98,11.05 and 17.12.Therefore,the liquid pulsation rate of the new hybrid actuator is significantly reduced,which is beneficial for improving the flow uniformity and weakening the influence of inertial force on the hybrid actuator.This strategy ultimately leads to a maximum no-load velocity of 168.1 mm/s at 600 Hz and a maximum blocking force of 141 N at 450 Hz for the new hybrid actuator.In addition,this strategy has the potential to be used in other electrohydrostatic actuators to improve their performance.

关键词： Double-acting Flow pulsation Inertial force Piezoelectric actuators Piezoelectric devices Piezoelectric hydraulic actuation Piezoelectric pump

High-performance liquid metal electromagnetic actuator fabricated by femtosecond laser

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International Journal of Extreme Manufacturing 2024年第2期6卷 511-521页

作者： Yiyu Chen Hao Wu Rui Li Shaojun Jiang Shuneng Zhou Zehang Cui Yuan Tao Xinyuan Zheng Qianqian Zhang Jiawen Li Guoqiang Li Dong Wu Jiaru Chu Yanlei Hu CAS key laboratory of Mechanical Behavior and Design of Materials Key Laboratory of Precision Scientific Instrumentation of Anhui Higher Education InstitutesDepartment of Precision Machinery and Precision InstrumentationUniversity of Science and Technology of ChinaHefei 230027People’s Republic of China key laboratory of Testing Technology for Manufacturing Process of Ministry of Education Southwest University of Science and TechnologyMianyang 621010People’s Republic of China Department of Mechanical Engineering The University of Hong KongHong Kong Special Administrative Region of ChinaPeople’s Republic of China

Small-scale electromagnetic soft actuators are characterized by a fast response and simplecontrol,holding prospects in the field of soft and miniaturized robotics.The use of liquid metal(LM)to replace a rigid conductor inside soft actuators can reduce the rigidity and enhance the actuation performance and robustness.Despite research efforts,challenges persist in the flexible fabrication of LM soft actuators and in the improvement of actuation performance.To address these challenges,we developed a fast and robust electromagnetic soft microplate actuator based on a laser-induced selective adhesion transfer method.Equipped with unprecedentedly thin LM circuit and customized low Young’s modulus silicone rubber(1.03 kPa),our actuator exhibits an excellent deformation angle(265.25?)and actuation bending angular velocity(284.66 rad·s^(-1)).Furthermore,multiple actuators have been combined to build an artificial gripper with a wide range of functionalities.Our actuator presents new possibilities for designing small-scaleartificial machines and supports advancements in ultrafast soft and miniaturized robotics.

关键词： soft actuators femtosecond laser liquid metal

Monitoring of Sweat pH and Dual-Mode Anti-Counterfeiting from Metal-Organic Framework-Based Multifunctional Gel

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Chinese Journal of Chemistry 2024年第5期42卷 491-498页

作者： Xiangnan Wang Hongli Zhang Jiahe Li Gang Zou key laboratory of precision and intelligent Chemistry School of Chemistry and Materials ScienceUniversity of Science and Technology of ChinaHefeiAnhui230026 China

Monitoring of sweat pH plays important roles in physiological health,nutritional balance,psychological stress,and sports performance.However,the combination of functional MOFs with phosphorescent material to acquire the real-time physiological information,as well as the application of dual mode anti-counterfeiting,has seldom been reported.Herein,we developed multifunctional gel films based on MOFs and phosphorescent dyes which responded to H+ions and the related mechanism was studied in detail.Upon exposure to H+,the composite gel film exhibited decreased fluorescent signal but enhanced room temperature phosphorescence(RTP),which could be utilized for sweat pH sensing through a dual-mode.Moreover,multifunctional gel films exhibited a potential application in information encryption and anti-counterfeiting by designing of stimulus responsive multiple patterns.This research provided a new avenue for portable and non-invasive sweat pH monitoring methods while also offering insights into stimulus-responsive multifunctional materials.

关键词： Metal–Organic Frameworks Room-temperature phosphorescence Fluorescence Sweat pH monitor Anti-counterfeiting Yttrium Polymer composites Luminescence

Single-step-etched ultra-compact metamaterial grating coupler enabled by a hierarchical inverse design approach

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 119-126页

作者： Qiao Wang Ruiqi Luo Nan Liu Maojing Hou Bo Xiong Guandong Liu Wei Ma intelligent Network Research Institute Zhejiang LabHangzhou 311100China State key laboratory of Modern Optical instrumentation College of Information Science and Electronic EngineeringZhejiang UniversityHangzhou 310027China

With the concept of metamaterials introduced into integrated photonics,subwavelength structures have gained popularity for their ability to create devices with ultra-compact size,high performance,and versatile functionalities.However,traditional metamaterial design methods are usually based on empirical templates and physical approximations,lacking the ability to design free-form metamaterial structures and optimize entire devices globally.In this work,we propose a hierarchical inverse design approach that combines a conventional effective refractive index based metamaterial structures design with a follow-up global topology optimization.The empirical metamaterial grating coupler design based on effective refractive index engineering faces inaccurate index extraction and insufficient approximation of wavevector matching conditions,which deteriorates coupling efficiency,especially for fully-etched devices with the decreased tapering region.Fortunately,a subsequent overall topology optimization step can well compensate for the negative effect of the shrinking device footprint to increase the efficiency of the metamaterial grating coupler.We demonstrate a 23μm×10μm ultra-compact metamaterial grating coupler with single-stepetched to couple light between a fiber and a 500 nm single-mode silicon waveguide in the O-band.Experimental measurement shows an insertion loss of 3.17 dB and a 3 dB bandwidth of 77 nm,making it the smallest footprint device ever reported.

关键词： waveguide hierarchical inverse

Solid-state atomic hydrogen as a broad-spectrum RONS scavenger for accelerated diabetic wound healing

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National Science Review 2024年第2期11卷 196-206页

作者： Man Luo Qin Wang Gang Zhao Wei Jiang Cici Zeng Qingao Zhang Ruyu Yang Wang Dong Yunxi Zhao Guozhen Zhang Jun Jiang Yucai Wang Qing Zhu key laboratory of precision and intelligent Chemistry School of Chemistry and Materials Science University of Science and Technology of China Department of Radiology The First Affiliated Hospital of University of Science and Technology of China Division of Life Sciences and Medicine University of Science and Technology of China Shenzhen Senior High School Institute of intelligent Innovation Henan Academy of Sciences

Hydrogen therapy shows great promise as a versatile treatment method for diseases associated with the overexpression of reactive oxygen and nitrogen species（RONS）. However, developing an advanced hydrogen therapy platform that integrates controllable hydrogen release, efficient RONS elimination, and biodegradability remains a giant technical challenge. In this study, we demonstrate for the first time that the tungsten bronze phase H0.53WO3（HWO） is an exceptionally ideal hydrogen carrier, with salient features including temperature-dependent highly-reductive atomic hydrogen release and broad-spectrum RONS scavenging capability distinct from that of molecular hydrogen. Moreover, its unique p H-responsive biodegradability ensures post-therapeutic clearance at pathological sites. Treatment with HWO of diabetic wounds in an animal model indicates that the solid-state atomic H promotes vascular formation by activating M2-type macrophage polarization and anti-inflammatory cytokine production, resulting in acceleration of chronic wound healing. Our findings significantly expand the basic categories of hydrogen therapeutic materials and pave the way for investigating more physical forms of hydrogen species as efficient RONS scavengers for clinical disease treatment.

关键词： atomic hydrogen RONS scavenger inflammatory regulation diabetic wound healing hydrogen therapy

Synthesis of ultra-High-Molecular-Weight Polyethylene by Transition-Metal-Catalyzed Precipitation Polymerization

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Precision Chemistry

precision Chemistry 2024年第2期2卷 63-69页

作者： Wenbing Wang Quan Wang Chen Zou Changle Chen key laboratory of precision and intelligent Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China

ultra-high-molecular-weight polyethylene(UHMWPE)plays an important role in many important fields as engineering plastics.In this contribution,a precipitation polymerization strategy is developed by combination of highly active phosphino-phenolate nickel catalysts with polymer-insoluble solvent(heptane)to access UHMWPE(Mn up to 8.3×10^(6)g mol^(-1))with good product morphology,free-flowing characteristics,and great mechanical properties.Compared with the academically commonly used aromatic solvent(toluene),the utilization of heptane offers simultaneous enhancement in important parameters including activity,polymer molecular weight,and catalyst thermal stability.This system can also generate polar functionalized UHMWPE with molecular weight of up to 1.6×10^(6)g mol^(-1)in the copolymerization of ethylene with polar comonomers.More importantly,this precipitation polymerization strategy is generally applicable to several representative transition metal catalyst systems,leading to UHMWPE synthesis with good product morphology control.

关键词： transition metal catalysts polyolefin UHMWPE precipitation polymerization polar monomer