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Active tuning of anisotropic phonon polaritons in natural van der Waals crystals with negative permittivity substrates and its application in energy transport

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Opto-Electronic Science 2024年第6期3卷 1-19页

作者： Shuo Chen xiaohu wu Ceji Fu LTCS and Department of Mechanics and Engineering Science College of EngineeringPeking UniversityBeijing 100871China Shandong Institute of Advanced Technology Jinan 250100China

Phonon polaritons(PhPs)exhibit directional in-plane propagation and ultralow losses in van der Waals(vdW)crystals,offering new possibilities for controlling the flow of light at the ***,these PhPs,including their directional propagation,are inherently determined by the anisotropic crystal structure of the host *** in-plane anisotropic PhPs can be manipulated by twisting engineering,such as twisting individual vdW slabs,dynamically adjusting their propagation presents a significant *** limited application of the twisted bilayer structure in bare films further restricts its *** this study,we present a technique in which anisotropic PhPs supported by bare biaxial vdW slabs can be actively tuned by modifying their local dielectric ***,we predict that the iso-frequency contour of PhPs can be reoriented to enable propagation along forbidden directions when the crystal is placed on a substrate with a moderate negative ***,we systematically investigate the impact of polaritonic coupling on near-field radiative heat transfer(NFRHT)between heterostructures integrated with different substrates that have negative *** main findings reveal that through the analysis of dispersion contour and photon transmission coefficient,the excitation and reorientation of the fundamental mode facilitate increased photon tunneling,thereby enhancing heat transfer between ***,the annihilation of the fundamental mode hinders heat ***,we find the enhancement or suppression of radiative energy transport depends on the relative magnitude of the slab thickness and the vacuum gap ***,the effect of negative permittivity substrates on NFRHT along the[001]crystalline direction ofα-MoO3 is *** spectral band where the excited fundamental mode resulting from the negative permittivity substrates is shifted to the first Reststrahlen Band(RB 1)ofα-MoO_(3) and

关键词： anisotropic phonon polaritons forbidden direction substrate with a negative permittivity near-field energy transport

Actively tuning anisotropic light-matter interaction in biaxial hyperbolic materialα-MoO_(3) using phase change material VO_(2) and graphene

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Chinese Physics B 2024年第4期33卷 631-638页

作者：周昆胡杨吴必园仲晓星吴小虎 School of Safety Engineering China University of Mining and TechnologyXuzhou 221116China Key Laboratory of Gas and Fire Control for Coal Mines China University of Mining and TechnologyXuzhou 221116China Shandong Institute of Advanced Technology Jinan 250100China School of Power and Energy Northwestern Polytechnical UniversityXi'an 710072China

Anisotropic hyperbolic phonon polaritons(PhPs)in natural biaxial hyperbolic materialα-MoO_(3) has opened up new avenues for mid-infrared nanophotonics,while active tunability ofα-MoO_(3) PhPs is still an urgent problem necessarily to be *** this study,we present a theoretical demonstration of actively tuningα-MoO_(3) PhPs using phase change material VO_(2) and *** is observed thatα-MoO_(3) PhPs are greatly dependent on the propagation plane angle of *** insulator-to-metal phase transition of VO_(2) has a significant effect on the hybridization PhPs of theα-MoO_(3)/VO_(2) structure and allows to obtain actively tunableα-MoO_(3) PhPs,which is especially obvious when the propagation plane angle of PhPs is ***,when graphene surface plasmon sources are placed at the top or bottom ofα-MoO_(3) inα-MoO_(3)/VO_(2)structure,tunable coupled hyperbolic plasmon-phonon polaritons inside its Reststrahlen bands(RB s)and surface plasmonphonon polaritons outside its RBs can be *** addition,the above-mentionedα-MoO_(3)-based structures also lead to actively tunable anisotropic spontaneous emission(SE)*** study may be beneficial for realization of active tunability of both PhPs and SE ofα-MoO_(3),and facilitate a deeper understanding of the mechanisms of anisotropic light-matter interaction inα-MoO_(3) using functional materials.

关键词： light-matter interaction hyperbolic material phase change material graphene

MXene Sediment-Based Poly(vinyl alcohol)/Sodium Alginate Aerogel Evaporator with Vertically Aligned Channels for Highly Efficient Solar Steam Generation

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Nano-Micro Letters 2024年第10期16卷 638-654页

作者： Tian Wang Meng Li Hongxing Xu Xiao Wang Mingshu Jia Xianguang Hou Shuai Gao Qingman Liu Qihang Yang Mingwei Tian Lijun Qu Zhenhua Song xiaohu wu Lili Wang Xiansheng Zhang Shandong Key Laboratory of Medical and Health Textile Materials College of Textiles and ClothingState Key Laboratory of Bio-Fibers and Eco-TextilesResearch Center for Intelligent and Wearable TechnologyQingdao UniversityQingdao 266071People's Republic of China Department of Pharmacology Qingdao University School of PharmacyQingdao UniversityQingdao 266071People's Republic of China Shandong Institute of Advanced Technology Jinan 250100People's Republic of China College of Electromechanical Engineering Qingdao University of Science and TechnologyQingdao 266061People's Republic of China

Solar-driven interfacial evaporation from seawater is considered an effective way to alleviate the emerging freshwater crisis because of its green and environmentally friendly ***,developing an evaporator with high efficiency,stability,and salt resistance remains a key ***,with an internal photothermal conversion efficiency of 100%,has received tremendous research interest as a photothermal ***,the process to prepare the MXene with monolayer is inefficient and generates a large amount of“waste”MXene sediments(MS).Here,MXene sediments is selected as the photothermal material,and a three-dimensional MXene sediments/poly(vinyl alcohol)/sodium alginate aerogel evaporator with vertically aligned pores by directional freezing method is innovatively *** vertical porous structure enables the evaporator to improve water transport,light capture,and high evaporation *** swabs and polypropylene are used as the water channel and support,respectively,thus fabricating a self-floating *** evaporator exhibits an evaporation rate of 3.6 kg m^(-2)h^(-1)under one-sun illumination,and 18.37 kg m^(-2)of freshwater is collected in the condensation collection device after 7 h of outdoor sun *** evaporator also displays excellent oil and salt *** research fully utilizes“waste”MS,enabling a self-floating evaporation device for freshwater collection.

关键词： MXene sediments Porous structure Desalination Self-floating

Influence of substrate effect on near-field radiative modulator based on biaxial hyperbolic materials

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Chinese Physics B 2024年第4期33卷 56-64页

作者：刘睿一刘皓佗胡杨崔峥吴小虎 Institute of Advanced Technology Shandong UniversityJinan 250061China Shandong Institute of Advanced Technology Jinan 250100China School of Power and Energy Northwestern Polytechnical UniversityXi'an 710072China

Relative rotation between the emitter and receiver could effectively modulate the near-field radiative heat transfer(NFRHT)in anisotropic *** to the strong in-plane anisotropy,natural hyperbolic materials can be used to construct near-field radiative modulators with excellent modulation ***,in practical applications,natural hyperbolic materials need to be deposited on the substrate,and the influence of substrate on modulation effect has not been studied *** this work,we investigate the influence of substrate effect on near-field radiative modulator based onα-MoO_(3).The results show that compared to the situation without a substrate,the presence of both lossless and lossy substrate will reduce the modulation contrast(MC)for different film *** the real or imaginary component of the substrate permittivity increases,the mismatch of hyperbolic phonon polaritons(HPPs)weakens,resulting in a reduction in *** reducing the real and imaginary components of substrate permittivity,the MC can be significantly improved,reaching 4.64 forε_(s)=3 at t=10 *** work indicates that choosing a substrate with a smaller permittivity helps to achieve a better modulation effect,and provides guidance for the application of natural hyperbolic materials in the near-field radiative modulator.

关键词： near-field radiative modulator substrate effect hyperbolic material modulation contrast

Near-field radiative heat transfer between nanoporous GaN films

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Chinese Physics B 2024年第4期33卷 109-120页

作者：韩晓政张纪红刘皓佗吴小虎冷惠文 School of Electromechanical and Automotive Engineering Yantai UniversityYantai 264005China Key Laboratory of Advanced Manufacturing and Intelligent Technology Ministry of EducationHarbin University of Science and TechnologyHarbin 150080China Thermal Science Research Center Shandong Institute of Advanced TechnologyJinan 250100China

Photon tunneling effects give rise to surface waves,amplifying radiative heat transfer in the near-field *** research has highlighted that the introduction of nanopores into materials creates additional pathways for heat transfer,leading to a substantial enhancement of near-field radiative heat transfer(NFRHT).Being a direct bandgap semiconductor,GaN has high thermal conductivity and stable resistance at high temperatures,and holds significant potential for applications in optoelectronic ***,study of NFRHT between nanoporous GaN films is currently lacking,hence the physical mechanism for adding nanopores to GaN films remains to be discussed in the field of *** this work,we delve into the NFRHT of GaN nanoporous films in terms of gap distance,GaN film thickness and the vacuum filling *** results demonstrate a 27.2%increase in heat flux for a 10 nm gap when the nanoporous filling ratio is ***,the spectral heat flux exhibits redshift with increase in the vacuum filling *** be more precise,the peak of spectral heat flux moves fromω=1.31×10^(14)rad·s^(-1)toω=1.23×10^(14)rad·s^(-1)when the vacuum filling ratio changes from f=0.1 to f=0.5;this can be attributed to the excitation of surface phonon *** introduction of graphene into these configurations can highly enhance the NFRHT,and the spectral heat flux exhibits a blueshift with increase in the vacuum filling ratio,which can be explained by the excitation of surface plasmon *** findings offer theoretical insights that can guide the extensive utilization of porous structures in thermal control,management and thermal modulation.

关键词： near-field radiative heat transfer nanoporous GaN film surface phonon polaritons surface plasmon polaritons

基于三维全参数反演的煤矿采空区形变提取方法研究

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煤炭科学技术 2024年第S01期52卷 22-29页

作者：刘晖李梅袁明泽姜展王金正吴小虎南京信息工程大学遥感与测绘工程学院江苏南京210044 南京信大安全应急管理研究院有限公司江苏南京211800 北京大学地球与空间科学学院遥感与地理信息系统研究所北京100871 中国人民解放军95806部队北京100076 山东能源鲁西矿业郭屯煤矿山东菏泽274700 山东高等技术研究院山东济南250100

准确提取地表形变信息对于预防和控制煤矿开采导致的地质灾害至关重要。以山东郭屯煤矿某工作面为例,首先获取了工作面开采时间段内(2017年7月31日至2018年5月3日)的18景Sen-tinel-1A卫星影像,基于SBAS-InSAR技术处理得到工作面采空区... 详细信息

准确提取地表形变信息对于预防和控制煤矿开采导致的地质灾害至关重要。以山东郭屯煤矿某工作面为例,首先获取了工作面开采时间段内(2017年7月31日至2018年5月3日)的18景Sen-tinel-1A卫星影像,基于SBAS-InSAR技术处理得到工作面采空区地表形变。在InSAR观测数据的驱动下,通过推导概率积分法与SBAS-InSAR视线向形变三维参数之间的函数映射关系,提出了一种基于随机误差消除遗传算法的三维全参数反演模型。基于该方法,准确反演了研究区地表沉降参数,通过与现场经验值对比,各参数的偏差均小于3%,拟合精度较高。最后,基于反演参数与概率积分法获得了采空区全盆地沉降形变信息,其中A测线与F测线的均方根误差分别为0.083 m和0.102 m,平均绝对误差分别为0.068 m和0.089 m,预计结果与实测水准测量数据高度一致,表明所提出的三维全参数反演模型能够以低成本的方式有效获取煤矿采空区全盆地沉降信息。

关键词：采空区沉降概率积分法 SBAS-InSAR 随机误差消除三维全参数反演

空间引力波星载望远镜测试与评估技术研究进展

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光电工程 2024年第2期51卷 7-23页

作者：张兰强曾意吴小虎杨金生阮晓莉辛强顾乃庭饶长辉自适应光学全国重点实验室中国科学院光电技术研究所中国科学院大学山东高等技术研究院

在空间引力波探测任务中，星载望远镜承担太空超长干涉光路双向光束准直的重要作用。空间引力波探测对星载望远镜提出了pm级光程稳定性和低于10-10级后向杂散光水平的极高要求。超高水平指标要求超过了当前测试技术的精度极限，因此，... 详细信息

在空间引力波探测任务中，星载望远镜承担太空超长干涉光路双向光束准直的重要作用。空间引力波探测对星载望远镜提出了pm级光程稳定性和低于10-10级后向杂散光水平的极高要求。超高水平指标要求超过了当前测试技术的精度极限，因此，针对星载望远镜发展测试与评估技术并开展系统超高精度测试是空间引力波探测计划成功的重要前提。本文在概述国内外在研的空间引力波探测星载望远镜研制情况的基础上，重点围绕星载望远镜的核心技术指标——光程稳定性和后向杂散光，介绍了在研望远镜的测试技术发展现状和已经取得的部分测试成果，以及各研究单位进一步的测试计划，为我国的空间引力波探测的星载望远镜测试与评估技术发展提供参考。

关键词：空间引力波探测星载望远镜地面测试光程稳定性后向杂散光

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高压GIS用三工位隔离接地开关的结构类型

高压电器 2024年第1期60卷 197-204页

作者：吴小虎吕东明高美华鄢敏杨清清宋鹏付杰川开电气有限公司成都610200 青岛特锐德电气股份有限公司山东青岛266000

文中介绍了72.5 kV及以上气体绝缘金属封闭开关设备(简称GIS)常用的3种结构类型的三工位隔离接地开关:双导电杆连杆传动的三工位隔离接地开关、滚珠丝杠传动的三工位隔离接地开关、齿轮齿条传动的三工位隔离接地开关。这3种三工位隔离... 详细信息

文中介绍了72.5 kV及以上气体绝缘金属封闭开关设备(简称GIS)常用的3种结构类型的三工位隔离接地开关:双导电杆连杆传动的三工位隔离接地开关、滚珠丝杠传动的三工位隔离接地开关、齿轮齿条传动的三工位隔离接地开关。这3种三工位隔离接地开关有别于传统的旋转闸刀式结构,都是属于国内外主流的动触头直动插入式结构。通过对这3种三工位隔离接地开关结构、滑动电联接形式以及运动形式的阐述,分析了各种结构的优势,为GIS核心模块部件的改进和优化设计提供技术指导。

关键词： GIS 三工位隔离接地开关双导电杆滚珠丝杠齿轮齿条

超高效液相色谱串联质谱法测定豇豆中新烟碱类农药残留

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植物保护 2024年第3期50卷 247-252,271页

作者：邱琦珍潘兴鲁吴小虎徐军董丰收郑永权天津农学院园艺园林学院天津300384 中国农业科学院植物保护研究所植物病虫害综合治理全国重点实验室北京100193

本研究建立了超高效液相色谱串联质谱法(UPLC-MS/MS)同时检测豇豆中9种新烟碱类杀虫剂的多残留分析方法。豇豆样品用QuEChERS方法前处理,用Kinetex Biphenyl色谱柱分离,以甲醇和含0.1 mmol/L甲酸铵、0.001%甲酸的水作为流动相进行梯度洗... 详细信息

本研究建立了超高效液相色谱串联质谱法(UPLC-MS/MS)同时检测豇豆中9种新烟碱类杀虫剂的多残留分析方法。豇豆样品用QuEChERS方法前处理,用Kinetex Biphenyl色谱柱分离,以甲醇和含0.1 mmol/L甲酸铵、0.001%甲酸的水作为流动相进行梯度洗脱,使用超高效液相色谱串联质谱检测分析。定量限为0.01 mg/kg,标准工作曲线在0.001~1 mg/kg范围内表现出良好的线性关系,决定系数(R^( 2))均大于0.99。目标杀虫剂在豇豆中的平均回收率为66.9%~109.8%,相对标准偏差为1.2%~10.0%。应用该方法对某地16个农贸市场中采集的71份豇豆样本进行检测,所有样品均符合我国所规定的豇豆(或豆类)中的最大残留限量标准要求。该方法简便、准确、灵敏度高,适用于新烟碱类杀虫剂在豇豆中的残留监测。

关键词：新烟碱类杀虫剂豇豆超高效液相色谱串联质谱残留检测