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里德堡原子雷达接收灵敏度极限

微波学报 2024年第2期40卷 1-7页

作者：夏凌昊肖俊祥董屾金翔赵盛至南京电子技术研究所南京210039 雷达探测感知全国重点实验室南京210039 江苏省探测感知技术重点实验室南京210039

里德堡原子在微波场的存在下呈现出电磁诱导透明效应,因而可用于微弱电场的探测。近年来,基于里德堡原子微波探测技术的新型雷达接收机架构引起了业内广泛关注。文中分析了里德堡原子雷达接收机的外部和内部噪声源,探究了里德堡原子接... 详细信息

里德堡原子在微波场的存在下呈现出电磁诱导透明效应,因而可用于微弱电场的探测。近年来,基于里德堡原子微波探测技术的新型雷达接收机架构引起了业内广泛关注。文中分析了里德堡原子雷达接收机的外部和内部噪声源,探究了里德堡原子接收机的灵敏度,指出在雷达侦收场景下,当前可制备的里德堡原子接收机灵敏度不及传统电子技术接收机,并针对里德堡原子雷达接收机的实用化提出了技术改进方案。

关键词：里德堡原子高灵敏度探测标准量子噪声极限

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基于粒子群算法的低轨重点卫星雷达协同探测任务规划方法

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现代雷达 2024年第6期46卷 108-114页

作者：陈冠任刘伟翟计全赵盛至张蒙夏凌昊南京电子技术研究所江苏南京210039 雷达探测感知全国重点实验室江苏南京210039 江苏省探测感知技术重点实验室江苏南京210039

为提升定轨、成像、目标特性测量等多种模式下的观测效率,基于粒子群算法提出了一种低轨重点卫星雷达观测任务规划方法。相较基于优先级的任务规划方法,文中方法可对所有卫星按给定观测频次无丢失观测,满足雷达视场、时间窗口、任务切... 详细信息

为提升定轨、成像、目标特性测量等多种模式下的观测效率,基于粒子群算法提出了一种低轨重点卫星雷达观测任务规划方法。相较基于优先级的任务规划方法,文中方法可对所有卫星按给定观测频次无丢失观测,满足雷达视场、时间窗口、任务切换等约束。使用雷达仰角、斜距、雷达截面积构建权值对基于观测时长的目标函数进行修改,并使用粒子群优化算法求解最大总观测时长或最快完成时间。仿真场景为两部假想地面雷达协同对30颗低轨重点卫星做24 h~72 h观测。结果表明,所有卫星无丢失观测,最大总观测时长和最快完成时间分别为18622 s和15 h 16 min(场景时间:24 h)。使用带有权值的目标函数可获得平均观测仰角、斜距的改善,而总观测时长基本一致。

关键词：任务规划低轨卫星空间目标监视雷达协同态势感知

Third-order nonlinear optical responses of CuO nanosheets for ultrafast pulse generation

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Journal of Materiomics 2022年第2期8卷 511-517页

作者： Li Dong Hongwei Chu Ying Li shengzhi zhao Dechun Li School of Information Science and Engineering Shandong UniversityQingdao266237China Key Laboratory of Colloid and Interface Chemistry Ministry of EducationSchool of Chemistry and Chemical EngineeringJinan250100China

As a representative transition metal oxide,cupric oxide(CuO)has attracted a lot of interest in miscel-laneous *** the present work,the prominent third-order nonlinear optical(NLO)features of CuO nanosheets were demonstrated via the typical Z-scan technique at 1 m *** open-aperture(OA)Z-scan measurements at different intensities clearly showed that CuO nanosheets possessed the saturable ab-sorption(SA),reverse saturable absorption(RSA)and optical limiting *** closed-aperture(CA)Z-scan technology was implanted to investigate the nonlinear refractive index and the third-order nonlinear *** virtue of the strong nonlinear optical absorption properties of CuO nano-sheets,a stable all-solid-state mode-locked laser with the as-prepared CuO nanosheets as saturable absorber at 1.06 m m was realized for the first *** work confirmed that CuO nanosheets exhibited outstanding NLO properties,which might stimulate the development in ultrafast photonics and nonlinear optics.

关键词： Transition metal oxide Nonlinear saturable absorption Nonlinear susceptibility Saturable absorber Mode-locking

Nonlinear optical properties of carboxyl-functionalized graphene oxide for dissipative soliton resonance pulse generation

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Journal of Materiomics 2023年第4期9卷 642-650页

作者： Han Pan Hongwei Chu Zhongben Pan Ying Li shengzhi zhao Dechun Li School of Information Science and Engineering Key Laboratory of Laser and Infrared System of Ministry of EducationShandong UniversityQingdao266237China Key Laboratory of Colloid and Interface Chemistry of State Education Ministry School of Chemistry and Chemical EngineeringShandong UniversityJinan250100China

Here,we investigated the nonlinear optical(NLO)characteristics of carboxyl-functionalized graphene oxide(GO-COOH)in the near-infrared(NIR)*** results revealed that GO-COOH samples exhibit strong saturable absorption at low pump levels and a gradual transition to reverse saturable absorption(RSA)with increasing pump *** the saturable absorber(SA)by depositing the GO-COOH on the side-polished fiber(SPF)was employed in Yb-and Er-doped fiber *** ultrashort pulses operating in the dissipative soliton(DS)and conventional soliton(CS)regimes were obtained with pulse widths of 26.6 ps and 968 fs,***,the dissipative soliton resonance(DSR)phenomenon caused by the RSA of GO-COOH was also observed with increasing pump *** high-stable DSR mode-locked pulses with the maximum pulse energy of 1.91 nJ and 0.74 nJ were obtained in YDFL and EDFL *** results not only reveal the potentiality of GO-COOH in ultrafast photonics applications but also open a new avenue to explore high-pulse-energy laser sources based on twodimensional materials.

关键词： Carboxyl-modified graphene oxide First-principles calculation Reverse saturable absorption Ultrafast fiber laser Saturable absorber Dissipative soliton resonance

Bismuthene quantum dots integrated D-shaped fiber as saturable absorber for multi-type soliton fiber lasers

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Journal of Materiomics 2023年第1期9卷 183-190页

作者： Han Pan Hongwei Chu Ying Li Zhongben Pan Jia zhao shengzhi zhao Weichun Huang Dechun Li School of Information Science and Engineering and Key Laboratory of Laser and Infrared System of Ministry of EducationShandong University72 Binhai RoadQingdao266237China Key Laboratory of Colloid and Interface Chemistry of State Education Ministry School of Chemistry and Chemical EngineeringShandong University27 Shanda South RoadJinan250100China School of Chemistry and Chemical Engineering Nantong University9 Seyuan RoadNantong226019China

In the present work,the uniformly sized bismuthene quantum dots(BiQDs)with an average diameter of 26 nm were fabricated via the solvothermal *** transferring the BiQDs onto the plane of micro-machined D-shaped fiber(DSF),a new type of saturable absorber(SA)was successfully *** on the evanescent field effect of D-shaped fiber,the prepared SA exhibits excellent saturable absorption properties with the maximum modulation depth of 5.1%at around 1.5μ*** further investigate its potential applications in ultrafast photonics,we demonstrated passive mode-locking operation in the erbium-doped fiber laser(EDFL)with BiQDs/*** conventional soliton pulses with duration of 835 fs at the repetition rate of 9.23 MHz and dissipative soliton pulses with duration of 575 fs at the repetition rate of 7.83 MHz were generated *** addition,stable bound state of solitons with the pulse duration of 1.04 ps and sub-pulse time interval of 15.9 ps were also obtained based on the conventional soliton state by adjusting the pump power and polarization *** work reveals the great potential and capacity of BiQDs/DSF-SA in soliton mode-locking operations and promotes the explorative investigation of bismuth-based optoelectronic devices.

关键词： Bismuthene quantum dots Saturable absorber Soliton mode-locking Bound-state solitons Ultrafast photonics

Short mid-infrared watt-level all-fiber nonlinear pulse compressor above 100-MHz pulse repetition rate

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High Power Laser Science and Engineering 2023年第1期11卷 107-113页

作者： Jingcheng Shang Chao Mei shengzhi zhao Yizhou Liu Kejian Yang Chun Wang Tao Li Tianli Feng School of Information Science and Engineering Shandong Provincial Key Laboratory of Laser Technology and ApplicationShandong UniversityQingdaoChina Key Laboratory of Laser&Infrared System(Shandong University) Ministry of EducationQingdaoChina Institute of Novel Semiconductors State Key Laboratory of Crystal MaterialsShandong UniversityJinanChina Beijing Engineering and Technology Center for Convergence Networks and Ubiquitous Services SCCEUniversity of Science and Technology BeijingBeijingChina

We firstly report a 2-μm all-fiber nonlinear pulse compressor based on two pieces of normal dispersion fiber(NDF),which enables a high-power scaling ability of watt-level and a high pulse compression ratio of *** the NDFbased all-fiber nonlinear pulse compressor,the 450-fs laser pulses with a repetition rate of 101.4 MHz are compressed to 35.1 fs,corresponding to a 5.2 optical oscillation cycle at the 2-μm wavelength *** output average power reaches 1.28 W,which is believed to be the highest value never achieved from the previous 2-μm all-fiber nonlinear pulse compressors with a high pulse repetition rate above 100 *** dynamic evolution of the ultrafast pulse inside the all-fiber nonlinear pulse compressor is numerically analyzed,matching well with the experimental results.

关键词： few-optical-cycle pulses high pulse repetition rate nonlinear pulse compression

VO_(x)/NaVO_(3) nanocomposite as a novel saturable absorber for passive Q-switching operation

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Chinese Optics Letters 2022年第5期20卷 24-28页

作者： Linghao Kong Hongwei Chu Na Li Han Pan shengzhi zhao Dechun Li School of Information Science and Engineering Shandong UniversityQingdao 266237China School of Physics and Technology University of JinanJinan 250022China

We report VO_(x)/NaVO_(3) nanocomposite as a novel saturable absorber for the first time,to the best of our *** efficient nonlinear absorption coefficient and the modulation depth are determined by the Z-scan *** a saturable absorber,a passively Q-switched Nd-doped bulk laser at 1.34μm is demonstrated,producing the shortest pulse duration of 129 ns at a repetition rate of 274 *** the passively Q-switched Tm:YLF laser with the prepared saturable absorber,the shortest pulse duration was 292 ns with a repetition rate of 155 *** work confirmed the saturable absorption in VO_(x)/NaVO_(3) for possible optical modulation in the near-infrared region.

关键词： nonlinear optical properties saturable absorber VO_(x)/NaVO_(3)composite O-switching

大跨度钢屋盖轮辐式索桁架结构施工方法与数值模拟

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施工技术（中英文） 2024年第8期53卷 8-12页

作者：张文津王康刘贵文孔祥凯赵生智高扬阴光华中国建筑第八工程局有限公司上海200135 同济大学土木工程学院上海200092

轮辐式张拉结构通过张拉柔性拉索形成刚度,抵抗结构所承受的外荷载。为保证柔性结构张拉成型全过程安全可靠、张拉完成后满足设计要求,对施工过程各阶段进行数值模拟和计算分析,确定合理的施工方案。采用有限元软件ANSYS建立济南市黄河... 详细信息

轮辐式张拉结构通过张拉柔性拉索形成刚度,抵抗结构所承受的外荷载。为保证柔性结构张拉成型全过程安全可靠、张拉完成后满足设计要求,对施工过程各阶段进行数值模拟和计算分析,确定合理的施工方案。采用有限元软件ANSYS建立济南市黄河体育中心钢屋盖轮辐式索桁架整体分析模型;通过等效降温法对轮辐式拉索施加预拉力,得到不同施工阶段整体结构力学响应;对索桁架结构展开形态分析,使索构件实际内力与设计拉力吻合。研究表明,采用等效降温法可实现对大跨度钢屋盖轮辐式拉索预拉力的模拟,整体结构在各施工阶段的力学响应满足安全性要求。

关键词：钢结构拉索张拉等效降温法有限元分析施工技术

Enhanced Q-switching performance of magnetite nanoparticle via compositional engineering with Ti_(3)C_(2) MXene in the near infrared region

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Journal of Materials Science & Technology 2021年第22期81卷 51-57页

作者： Yutao Hu Hongwei Chu Daozhi Li Ying Li shengzhi zhao Li Dong Dechun Li School of Information Science and Engineering Shandong UniversityQingdao266237China Key Laboratory of Colloid and Interface Chemistry Ministry of Educationand School of Chemistry and Chemical EngineeringShandong UniversityJinan250100China

In this work,we reported a new strategy to improve the nonlinear saturable absorption performance of magnetite(Fe_(3)O_(4))nanoparticles(FONPs)via the compositional engineering with the Ti_(3)C_(2) MXene in the near-infrared(NIR)*** on the DFT simulation,the band structures and work function were significantly modified by the Ti_(3)C_(2) MXene *** using the open-aperture Z-scan technology,the nonlinear optical features of the FONPs@Ti_(3)C_(2) nanocomposite were significantly improved,showing the great potential as the saturable absorber in the pulsed *** the nanocomposite as the saturable absorber,the passively Q-switched Nd:GdVO4 lasers emitted much shorter pulse durations when compared with the pristine FONP saturable *** findings indicated that FONPs@Ti_(3)C_(2) heterostructure was a promising saturable absorber for the short pulse generation in the NIR region.

关键词： Fe_(3)O_(4)nanoparticle Ti_(3)C_(2)Mxene Heterostructure Saturable absorber Q-switching