检索结果-内蒙古大学图书馆

Active Photonic Platforms XII 2020

作者： Shalaginov, Mikhail Y. An, Sensong Zhang, Yifei Yang, Fan Su, Peter Liberman, Vladimir Chou, Jeffrey B. Roberts, Christopher M. Kang, Myungkoo Rios, Carlos Du, Qingyang Fowler, Clayton Agarwal, Anuradha Richardson, Kathleen A. Rivero-Baleine, Clara Zhang, Hualiang Hu, Juejun Gu, Tian Department of Materials Science and Engineering Massachusetts Institute of Technology CambridgeMA02139 United States Department of Electrical and Computer Engineering University of Massachusetts Lowell LowellMA United States Lincoln Laboratory Massachusetts Institute of Technology LexingtonMA United States College of Optics and Photonics Department of Materials Science and Engineering University of Central Florida OrlandoFL United States Missiles and Fire Control Lockheed Martin Corporation OrlandoFL United States

ISBN: (纸本)9781510637283

Optical metasurfaces, planar sub-wavelength nano-antenna arrays with the singular ability to sculpt wave front in almost arbitrary manners, are poised to become a powerful tool enabling compact and high-performance optics with novel functionalities. A particularly intriguing research direction within this field is active metasurfaces, whose optical response can be dynamically tuned post-fabrication, thus allowing a plurality of applications unattainable with traditional bulk optics. The efforts to date, however, still face major performance limitations in tuning range, optical quality, and efficiency especially for non-mechanical actuation mechanisms. In this paper, we introduce an active metasurface platform combining phase tuning covering the full 2 range and diffraction-limited performance using an all-dielectric, low-loss architecture based on optical phase change materials (O-PCMs). We present a generic design principle enabling binary switching of metasurfaces between arbitrary phase profiles. We implement the approach to realize a high-performance varifocal metalens. The metalens is constructed using Ge2Sb2Se4Te1 GSST), an O-PCM with a large refractive index contrast and unique broadband low-loss characteristics in both amorphous and crystalline states. The reconfigurable metalens features focusing efficiencies above 20 at both states for linearly polarized light and a record large switching contrast ratio (CR) close to 30 dB. We further validate aberration-free and multi-depth imaging using the metalens, which represents the first experimental demonstration of a non-mechanical active metalens with diffraction-limited performance © 2020 SPIE. All rights reserved.

关键词： Phase change materials

来源：评论

学校读者我要写书评

暂无评论

Perturbative countersurveillance metaoptics with compound nanosieves

引用

Light(science & Applications) 2019年第1期8卷 236-245页

作者： Jiancai Xue Zhang-Kai Zhou Limin Lin Chao Guo Shang Sun Dangyuan Lei Cheng-Wei Qiu Xue-Hua Wang State Key Laboratory of Optoelectronic Materials and Technologies School of PhysicsSun Yat-sen University510275 GuangzhouChina Department of Electrical and Computer Engineering National University of Singapore4 Engineering Drive 3Singapore 117583Singapore Department of Materials Science and Engineering City University of Hong Kong83 Tat Chee AvenueKowloonHong Kong

The progress of metaoptics relies on identifying photonic materials and geometries,the combination of which represents a promising approach to complex and desired optical *** candidate options are primarily limited by natural ***,the search for meta-atom geometries,by either forward or inverse means,plays a pivotal role in achieving more sophisticated *** efforts mainly focused on building the geometric library of individual meta-atoms and synthesizing various ones into a ***,those efforts neglected the powerfulness of perturbative metaoptics due to the perception that perturbations are usually regarded as adverse and in need of being ***,we report a perturbation-induced countersurveillance strategy using compound nanosieves mediated by structural and thermal *** information can be almost perfectly concealed and camouflaged by the induced thermal-spectral drifts,enabling information storage and exchange in a covert *** perturbative metaoptics can self-indicate whether the hidden information has been attacked during *** results establish a perturbative paradigm of securing a safer world of information and internet of things.

关键词： optics sieve compound

来源：评论

学校读者我要写书评

暂无评论

High-speed visible light communication based on micro-LED:A technology with wide applications in next generation communication

引用

Opto-Electronic science 2022年第12期1卷 11-34页

作者： Tingwei Lu Xiangshu Lin Wenan Guo Chang-Ching Tu Shibiao Liu Chun-Jung Lin Zhong Chen Hao-Chung Kuo Tingzhu Wu School of Electronic Science and Engineering Fujian Engineering Research Center for Solid-State LightingXiamen UniversityXiamen 361005China Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(IKKEM) Xiamen 361005China Department of Photonics and Graduate Institute of Electro-Optical Engineering College of Electrical and Computer EngineeringYang Ming Chiao Tung UniversityHsinchu 30010TaiwanChina Semiconductor Research Center Hon Hai Research InstituteTaipei 11492TaiwanChina Guangdong Visible Light Communication Technology Co. LTD.Foshan 528000China

The evolution of next-generation cellular networks is aimed at creating faster,more reliable *** the next-generation 6G network and the metaverse require high transmission *** light communication(VLC)is deemed an important ancillary technology to wireless *** has shown potential for a wide range of applications in next-generation *** light-emitting diodes(μLEDs)are ideal light sources for high-speed VLC,owing to their high modulation *** this review,an overview ofμLEDs for VLC is *** to improve the modulation bandwidth are discussed in terms of epitaxy optimization,crystal orientation,and active region ***,electroluminescent white LEDs,photoluminescent white LEDs based on phosphor or quantum-dot color conversion,andμLED-based detectors for VLC are ***,the latest high-speed VLC applications and the application prospects of VLC in 6G are introduced,including underwater VLC and artificial intelligence-based VLC systems.

关键词： visible light communication μLEDs modulation bandwidth detector 6G

来源：评论

学校读者我要写书评

暂无评论

An Adaptive Data Rate-Based Task Offloading Scheme in Vehicular Networks

An Adaptive Data Rate-Based Task Offloading Scheme in Vehicu...

引用

International Conference on Mobile Ad-hoc and Sensor Networks, MSN

作者： Chaofan Chen Wendi Nie Yaoxin Duan Victor C.S. Lee Kai Liu Huamin Li School of Automation Chongqing University Chongqing China Key Laboratory of Industrial Internet of Things and Networked Control Ministry of Education Chongqing China Department of Automation Chongqing University of Posts and Telecommunications Chongqing China Institute of Industrial Internet Chongqing University of Posts and Telecommunications Chongqing China Department of Electrical and Electronic Engineering the University of Hong Kong Hong Kong China College of Computer Science Chongqing University Chongqing China

As an important application of Internet of Things (IoT), Internet of Vehicles (IoVs) can provide various valuable services which may require computation-intensive tasks under strict time constraints. Most traditional vehicles may not be able to process all these computation-intensive tasks locally because of the limitation of computing resources. Therefore, task offloading has been proposed, which allows vehicles to offload computation-intensive tasks to Mobile Edge Computing (MEC) servers. With the arising and development of intelligent vehicles, the concept of Vehicle as a Resource (VaaR) has been proposed as an important supplement to MEC, which enables intelligent vehicles to share computation resources with nearby vehicles. Most studies in VaaR generally assume that the transmission data rate of offloading tasks from one vehicle to another is fixed. However, in VaaR, due to the high mobility of vehicles, the communication distance between vehicles may change over time, resulting in changing data rate. Therefore, it is challenging to make offloading decisions (i.e., selecting proper vehicles as computation resource providers) while considering adaptive data rate. In this paper, we study task offloading in vehicular networks while considering adaptive data rate. We propose an Adaptive Data Rate-based Offloading algorithm named ADRO, which can not only achieve minimum energy consumption while satisfying time constraints, but also take adaptive data rate into consideration. Comprehensive experiments have been conducted to demonstrate the efficiency of the ADRO algorithm.

关键词： Energy consumption Adaptive systems Multi-access edge computing Intelligent vehicles Sensors Time factors Servers

来源：评论

学校读者我要写书评

暂无评论

A hybrid volume-surface integral equation method for rapid electromagnetic simulations in MRI

arXiv

引用

arXiv 2022年

作者： Giannakopoulos, Ilias I. Guryev, Georgy D. Serrallés, José E.C. Paška, Jan Zhang, Bei Daniel, Luca White, Jacob K. Collins, Christopher M. Lattanzi, Riccardo The Bernard and Irene Schwartz Center for Biomedical Imaging Department of Radiology New York University Grossman School of Medicine NY10016 United States The Advanced Imaging Research Center UT Southwestern Medical Center 2201 Inwood Rd DallasTX75390 United States The Research Laboratory of Electronics Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology CambridgeMA02139 United States

Objective: We developed a hybrid volume surface integral equation (VSIE) method based on domain decomposition to perform fast and accurate magnetic resonance imaging (MRI) simulations that include both remote and local conductive elements. Methods: We separated the conductive surfaces present in MRI setups into two domains and optimized electromagnetic (EM) modeling for each case. Specifically, interactions between the body and EM waves originating from local radiofrequency (RF) coils were modeled with the precorrected fast Fourier transform, whereas the interactions with remote conductive surfaces (RF shield, scanner bore) were modeled with a novel cross tensor train-based algorithm. We compared the hybrid-VSIE with other VSIE methods for realistic MRI simulation setups. Results: The hybrid-VSIE was the only practical method for simulation using 1 mm voxel isotropic resolution (VIR). For 2 mm VIR, our method could be solved at least 23 times faster and required 760 times lower memory than traditional VSIE methods. Conclusion: The hybrid-VSIE demonstrated a marked improvement in terms of convergence times of the numerical EM simulation compared to traditional approaches in multiple realistic MRI scenarios. Significance: The efficiency of the novel hybrid-VSIE method could enable rapid simulations of complex and comprehensive MRI setups. © 2022, CC BY.

关键词： Magnetic resonance imaging

来源：评论

学校读者我要写书评

暂无评论

Observation of the dual quantum spin Hall insulator by density-tuned correlations in a van der Waals monolayer

arXiv

引用

arXiv 2024年

作者： Tang, Jian Ding, Thomas Siyuan Chen, Hongyu Gao, Anyuan Qian, Tiema Huang, Zumeng Sun, Zhe Han, Xin Strasser, Alex Li, Jiangxu Geiwitz, Michael Shehabeldin, Mohamed Belosevich, Vsevolod Wang, Zihan Wang, Yiping Watanabe, Kenji Taniguchi, Takashi Bell, David C. Wang, Ziqiang Fu, Liang Zhang, Yang Qian, Xiaofeng Burch, Kenneth S. Shi, Youguo Ni, Ni Chang, Guoqing Xu, Su-Yang Ma, Qiong Department of Physics Boston College Chestnut HillMA United States Division of Physics and Applied Physics School of Physical and Mathematical Sciences Nanyang Technological University Singapore Singapore Department of Chemistry and Chemical Biology Harvard University CambridgeMA United States Department of Physics and Astronomy and California NanoSystems Institute University of California Los Angeles Los AngelesCA United States Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing China Department of Materials Science and Engineering Texas A&M University College StationTX United States Department of Physics and Astronomy University of Tennessee KnoxvilleTN United States Min H. Kao Department of Electrical Engineering and Computer Science University of Tennessee KnoxvilleTN United States Research Center for Electronic and Optical Materials National Institute for Materials Science Tsukuba Japan Research Center for Materials Nanoarchitectonics National Institute for Materials Science Tsukuba Japan Harvard John A. Paulson School of Engineering and Applied Sciences The Center for Nanoscale system Harvard University CambridgeMA United States Department of Physics Massachusetts Institute of Technology CambridgeMA United States CIFAR Azrieli Global Scholars program CIFAR Toronto Canada

The convergence of topology and correlations represents a highly coveted realm in the pursuit of novel quantum states of matter [1, 2]. Introducing electron correlations to a quantum spin Hall (QSH) insulator can lead to the emergence of a fractional topological insulator and other exotic time-reversal-symmetric topological order [3- 10], not possible in quantum Hall and Chern insulator systems. However, the QSH insulator with quantized edge conductance remains rare, let alone that with significant correlations. In this work, we report a novel dual QSH insulator within the intrinsic monolayer crystal of TaIrTe4, arising from the interplay of its single-particle topology and density-tuned electron correlations. At charge neutrality, monolayer TaIrTe4 demonstrates the QSH insulator that aligns with single-particle band structure calculations, manifesting enhanced nonlocal transport and quantized helical edge conductance. Interestingly, upon introducing electrons from charge neutrality, TaIrTe4 only shows metallic behavior in a small range of charge densities but quickly goes into a new insulating state, entirely unexpected based on TaIrTe4's single-particle band structure. This insulating state could arise from a strong electronic instability near the van Hove singularities (VHS), likely leading to a charge density wave (CDW). Remarkably, within this correlated insulating gap, we observe a resurgence of the QSH state, marked by the revival of nonlocal transport and quantized helical edge conduction. Our observation of helical edge conduction in a CDW gap could bridge spin physics and charge orders. The discovery of a dual QSH insulator introduces a new method for creating topological flat minibands via CDW superlattices, which offer a promising platform for exploring time-reversal-symmetric fractional phases and electromagnetism [3-5, 11, 12]. Copyright © 2024, The Authors. All rights reserved.

关键词： Charge density waves

来源：评论

学校读者我要写书评

暂无评论

A Learning Convolutional Neural Network Approach for Network Robustness Prediction

arXiv

引用

arXiv 2022年

作者： Lou, Yang Wu, Ruizi Li, Junli Wang, Lin Li, Xiang Chen, Guanrong The Department of Computing and Decision Sciences Lingnan University Hong Kong The Key Laboratory of System Control and Information Processing Ministry of Education of China Shanghai200240 China The College of Computer Science Sichuan Normal University Chengdu610066 China The Department of Automation Shanghai Jiao Tong University Shanghai200240 China The Institute of Complex Networks and Intelligent Systems Shanghai Research Institute for Intelligent Autonomous Systems Tongji University Shanghai201210 China The Department of Control Science and Engineering Tongji University Shanghai200240 China The Department of Electrical Engineering City University of Hong Kong Hong Kong

Network robustness is critical for various societal and industrial networks again malicious attacks. In particular, connectivity robustness and controllability robustness reflect how well a networked system can maintain its connectedness and controllability against destructive attacks, which can be quantified by a sequence of values that record the remaining connectivity and controllability of the network after a sequence of node- or edge-removal attacks. Traditionally, robustness is determined by attack simulations, which are computationally very time-consuming or even practically infeasible. In this paper, an improved method for network robustness prediction is developed based on learning feature representation using convolutional neural network (LFR-CNN). In this scheme, higher-dimensional network data are compressed to lower-dimensional representations, and then passed to a CNN to perform robustness prediction. Extensive experimental studies on both synthetic and real-world networks, both directed and undirected, demonstrate that 1) the proposed LFR-CNN performs better than other two state-of-the-art prediction methods, with significantly lower prediction errors;2) LFR-CNN is insensitive to the variation of the network size, which significantly extends its applicability;3) although LFR-CNN needs more time to perform feature learning, it can achieve accurate prediction faster than attack simulations;4) LFR-CNN not only can accurately predict network robustness, but also provides a good indicator for connectivity robustness, better than the classical spectral measures. © 2022, CC BY.

关键词： Complex networks

来源：评论

学校读者我要写书评

暂无评论

Quantum simulation of superdiffusion breakdown in Heisenberg chains via 2D interactions

arXiv

引用

arXiv 2025年

作者： Kumaran, Keerthi Sajjan, Manas Pokharel, Bibek Gibbs, Joe Cohn, Jeffrey Jones, Barbara Mostame, Sarah Kais, Sabre Banerjee, Arnab Department of Physics and Astronomy Purdue University West LafayetteIN47907 United States Quantum Science Center Oak Ridge National Laboratory Oak RidgeTN37831 United States Department of Chemistry Purdue University West LafayetteIN47907 United States Department of Electrical and Computer Engineering North Carolina State University RaleighNC27606 United States IBM Quantum IBM T.J. Watson Research Center Yorktown Heights NY10598 United States School of Mathematics and Physics University of Surrey GuildfordGU2 7XH United Kingdom AWE Aldermaston ReadingRG7 4PR United Kingdom

Observing superdiffusive scaling in the spin transport of the integrable 1D Heisenberg model is one of the key discoveries in non-equilibrium quantum many-body physics. Despite this remarkable theoretical development and the subsequent experimental observation of the phenomena in KCuF3, real materials are often imperfect and contain integrability breaking interactions. Understanding the effect of such terms on the superdiffusion is crucial in identifying connections to such materials. Current quantum hardware has already ascertained its utility in studying such non-equilibrium phenomena by simulating the superdiffusion of the 1D Heisenberg model. In this work, we perform a quantum simulation of the superdiffusion breakdown by generalizing the superdiffusive Floquet-type 1D model to a general 2D model. We comprehensively study the effect of different 2D interactions on the superdiffusion breakdown by tuning up their strength from zero, corresponding to the 1D Heisenberg chain, to higher values. We observe that certain 2D interactions are more resilient against superdiffusion breakdown than others and that the SU(2) preserving 2D interaction has the highest resilience among all the 2D interactions we study. We observe that the location and multitude of the 2D interactions of a certain type do not change the relative resilience, but simply affect the time of onset of the breakdown. The superdiffusion breakdown was also captured in quantum hardware with remarkable accuracy, further establishing the quantum computer’s applicability in simulating interesting non-equilibrium quantum many-body phenomena. © 2025, CC BY.

关键词： Quantum computers

来源：评论

学校读者我要写书评

暂无评论

Prototype framework of low-latency collection of multi-point video stream over multi-hop multi-channel wireless network 9

Prototype framework of low-latency collection of multi-point...

引用

2019 9th International Workshop on computer science and engineering, WCSE 2019 SPRING

作者： Htut, Aung Myo Kim, Juseong Kim, JongWon Aswakul, Chaodit Wireless Network and Future Internet Research Unit Department of Electrical Engineering Faculty of Engineering Chulalongkorn University Bangkok Thailand Laboratory School of Electrical Engineering and Computer Science Gwangju Institute of Science and Technology Gwangju Korea Republic of

ISBN: (纸本)9789811414558

Big cities are facing heavy road traffic congestion. The main reason is the increasing number of vehicles beyond the road network capacity, which forces traffic police at times to be incapable of controlling the inevitable traffic jams. To resolve those traffic jams, traffic police need the near real-time information of the road network e.g. from traffic cameras. In this paper, a prototype framework of low-latency collection of multi-point video streams over a multi-hop multi-channel wireless network is proposed. Video frames are captured by Raspberry Pi cameras and sent by the wireless link to the herein-called IoT Concentrators. IoT-Cloud Hub then pulls and stores those video frames from the IoT Concentrators. Users (traffic police) can watch traffic videos from the display screen of the IoT-Cloud Hub. As a proof-of-concept implementation, two Pi Cameras have been set up with Apache Kafka Producers and two additional Raspberry Pi’s have been set up as the IoT Concentrators, which run the leader and follower Apache Kafka Brokers. To complete our system, an Intel® NUC as IoT-Cloud Hub and another Intel® NUC as Orchestration-Hub have been also set up. We assume the available wired communication linkage between the Orchestration-Hub and the other devices. However, the links between the Pi Cameras, IoT Concentrators and IoT-Cloud Hub are wireless with Wi-Fi. To achieve a high performance, multiple Wi-Fi channels can be dynamically configured by the Orchestration-Hub to steer the VDO traffic (based on TCP) away from the congested channels. Based on the implementation prototype, the average TCP throughputs over all the wireless links have been improved by 56.046% on average, compared with the case without the dynamic Wi-Fi channel selection. © Proceedings of 2019 the 9th International Workshop on computer science and engineering, WCSE 2019 SPRING. All rights reserved.

关键词： Video streaming

来源：评论

学校读者我要写书评

暂无评论

Skyrmions in nanorings: a versatile platform for Skyrmionics

arXiv

引用

arXiv 2023年

作者： Kechrakos, Dimitris Puliafito, Vito Riveros, Alejandro Liu, Jiahao Jiang, Wanjun Carpentieri, Mario Tomasello, Riccardo Finocchio, Giovanni Athens Greece Department of Electrical and Information Engineering Technical University of Bari Bari70125 Italy Escuela de Ingeniería Universidad Central de Chile Santiago8330601 Chile Department of Mathematical and Computer Sciences Physical Sciences and Earth Sciences University of Messina MessinaI-98166 Italy State Key Laboratory of Low-Dimensional Quantum Physics Department of Physics Tsinghua University Beijing100084 China Frontier Science Center for Quantum Information Tsinghua University Beijing100084 China College of Advanced Interdisciplinary Studies & Hunan Provincial Key Laboratory of Novel Nano-Optoelectronic Information Materials and Devices National University of Defense Technology Hunan Changsha410073 China

The dynamical properties of skyrmions can be exploited to build devices with new functionalities. Here, we first investigate a skyrmion-based ring-shaped device by means of micromagnetic simulations and Thiele’s equation. We subsequently show three applications scenarios: (1) a clock with tunable frequency that is biased with an electrical current having a radial spatial distribution, (2) an alternator, where the skyrmion circular motion driven by an engineered anisotropy gradient is converted into an electrical signal, and (3) an energy harvester, where the skyrmion motion driven by a thermal gradient is converted into an electrical signal, thus providing a heat recovery operation. We also show how to precisely tune the frequency and amplitude of the output electrical signals by varying material parameters, geometrical parameters, number and velocity of skyrmions, and we further prove the correct device functionality under realistic conditions given by room temperature and internal material defects. Our results open a new route for the realization of energy efficient nanoscale clocks, generators, and energy harvesters. © 2023, CC BY.

关键词： Clocks

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：