检索结果-内蒙古大学图书馆

arXiv 2023年

作者： Guo, Ziqi Niu, Yong Mao, Shiwen Zhang, Changming Wang, Ning Zhong, Zhangdui Ai, Bo The State Key Laboratory of Advanced Rail Autonomous Operation Beijing Jiaotong University Beijing100044 China The Collaborative Innovation Center of Railway Traffic Safety Beijing Jiaotong University Beijing100044 China The Department of Electrical and Computer Engineering Auburn University AuburnAL36849-5201 United States The Research Institute of Intelligent Networks Zhejiang Lab Hangzhou311121 China The School of Information Engineering Zhengzhou University Zhengzhou450001 China The Beijing Engineering Research Center of High-speed Railway Broadband Mobile Communications Beijing Jiaotong University Beijing100044 China

The concept of age of information (AoI) has been proposed to quantify information freshness, which is crucial for time-sensitive applications. However, in millimeter wave (mmWave) communication systems, the link blockage caused by obstacles and the severe path loss greatly impair the freshness of information received by the user equipments (UEs). In this paper, we focus on reconfigurable intelligent surface (RIS)-assisted mmWave communications, where beamforming is performed at transceivers to provide directional beam gain and a RIS is deployed to combat link blockage. We aim to maximize the system sum rate while satisfying the information freshness requirements of UEs by jointly optimizing the beamforming at transceivers, the discrete RIS reflection coefficients, and the UE scheduling strategy. To facilitate a practical solution, we decompose the problem into two subproblems. For the first per-UE data rate maximization problem, we further decompose it into a beamforming optimization subproblem and a RIS reflection coefficient optimization subproblem. Considering the difficulty of channel estimation, we utilize the hierarchical search method for the former and the local search method for the latter, and then adopt the block coordinate descent (BCD) method to alternately solve them. For the second scheduling strategy design problem, a low-complexity heuristic scheduling algorithm is designed. Simulation results show that the proposed algorithm can effectively improve the system sum rate while satisfying the information freshness requirements of all UEs. Copyright © 2023, The Authors. All rights reserved.

关键词： Scheduling algorithms

来源：评论

学校读者我要写书评

暂无评论

Ultrastrong Light-Matter Coupling in 2D Metal- Chalcogenates

arXiv

引用

arXiv 2023年

作者： Anantharaman, Surendra B. Lynch, Jason Aleksich, Mariya Stevens, Christopher E. Munley, Christopher Choi, Bongjun Shenoy, Sridhar Darlington, Thomas Majumdar, Arka Shuck, P. James Hendrickson, Joshua Hohman, J. Nathan Jariwala, Deep Department of Electrical and Systems Engineering University of Pennsylvania PhiladelphiaPA19104 United States Institute of Materials Science University of Connecticut StorrsCT06269 United States Department of Chemistry University of Connecticut StorrsCT06269 United States KBR Inc. BeavercreekOH45431 United States Air Force Research Laboratory Sensors Directorate Wright-Patterson Air Force Base OH45433 United States Department of Physics University of Washington SeattleWA98195 United States Department of Mechanical Engineering Columbia University New YorkNY10027 United States Department of Electrical and Computer Engineering University of Washington SeattleWA98195 United States

Hybridization of excitons with photons to form hybrid quasiparticles, exciton-polaritons (EPs), has been widely investigated in a range of semiconductor material systems coupled to photonic cavities. Self-hybridization occurs when the semiconductor itself can serve as the photonic cavity medium resulting in strongly-coupled EPs with Rabi splitting energies (ħΩ) > 200 meV at room temperatures which recently were observed in layered two-dimensional (2D) excitonic materials. Here, we report an extreme version of this phenomenon, an ultrastrong EP coupling, in a nascent, 2D excitonic system, the metal organic chalcogenate (MOCHA) compound named mithrene. The resulting self-hybridized EPs in mithrene crystals placed on Au substrates show Rabi Splitting in the ultrastrong coupling range (ħΩ > 600 meV) due to the strong oscillator strength of the excitons concurrent with the large refractive indices of mithrene. We further show bright EP emission at room temperature as well as EP dispersions at low-temperatures. Importantly, we find lower EP emission linewidth narrowing to ~1 nm when mithrene crystals are placed in closed Fabry-Perot cavities. Our results suggest that MOCHA materials are ideal for polaritonics in the deep green-blue part of the spectrum where strong excitonic materials with large optical constants are notably scarce. © 2023, CC BY.

关键词： Excitons

来源：评论

学校读者我要写书评

暂无评论

Intelligent metasurface imager and recognizer

引用

Light(Science & Applications) 2019年第1期8卷 297-305页

作者： Lianlin Li Ya Shuang Qian Ma Haoyang Li Hanting Zhao Menglin Wei Che Liu Chenglong Hao Cheng-Wei Qiu Tie Jun Cui State Key Laboratory of Advanced Optical Communication Systems and Networks Department of ElectronicsPeking UniversityBeijing 100871China State Key Laboratory of Millimeter Waves Southeast UniversityNanjing 210096China Department of Electrical and Computer Engineering National University of Singapore4 Engineering Drive 3117583 SingaporeSingapore

There is an increasing need to remotely monitor people in daily life using radio-frequency probe ***,conventional systems can hardly be deployed in real-world settings since they typically require objects to either deliberately cooperate or carry a wireless active device or identification *** accomplish complicated successive tasks using a single device in real time,we propose the simultaneous use of a smart metasurface imager and recognizer,empowered by a network of artificial neural networks(ANNs)for adaptively controlling data ***,three ANNs are employed in an integrated hierarchy,transforming measured microwave data into images of the whole human body,classifying specifically designated spots(hand and chest)within the whole image,and recognizing human hand signs instantly at a Wi-Fi frequency of 2.4 *** in situ full-scene imaging and adaptive recognition of hand signs and vital signs of multiple non-cooperative people were experimentally *** also show that the proposed intelligent metasurface system works well even when it is passively excited by stray Wi-Fi signals that ubiquitously exist in our daily *** reported strategy could open up a new avenue for future smart cities,smart homes,human-device interaction interfaces,health monitoring,and safety screening free of visual privacy issues.

关键词： image smart successive

来源：评论

学校读者我要写书评

暂无评论

Neural Network Methods for Radiation Detectors and Imaging

arXiv

引用

arXiv 2023年

作者： Lin, S. Ning, S. Zhu, H. Zhou, T. Morris, C.L. Clayton, S. Cherukara, M. Chen, R.T. Wang, Z. Los Alamos National Laboratory Los AlamosNM87545 United States Department of Electrical and Computer Engineering The University of Texas at Austin AustinTX78705 United States Center for Nanoscale Materials Argonne National Laboratory LemontIL60439 United States Advanced Photon Source Argonne National Laboratory LemontIL60439 United States Microelectronics Research Center The University of Texas at Austin AustinTX78758 United States Omega Optics Inc. AustinTX78757 United States

Recent advances in image data processing through machine learning and especially deep neural networks (DNNs) allow for new optimization and performance-enhancement schemes for radiation detectors and imaging hardware through data-endowed artificial intelligence. We give an overview of data generation at photon sources, deep learning-based methods for image processing tasks, and hardware solutions for deep learning acceleration. Most existing deep learning approaches are trained offline, typically using large amounts of computational resources. However, once trained, DNNs can achieve fast inference speeds and can be deployed to edge devices. A new trend is edge computing with less energy consumption (hundreds of watts or less) and real-time analysis potential. While popularly used for edge computing, electronic-based hardware accelerators ranging from general purpose processors such as central processing units (CPUs) to application-specific integrated circuits (ASICs) are constantly reaching performance limits in latency, energy consumption, and other physical constraints. These limits give rise to next-generation analog neuromorhpic hardware platforms, such as optical neural networks (ONNs), for high parallel, low latency, and low energy computing to boost deep learning acceleration. (LA-UR-23-32395) Copyright © 2023, The Authors. All rights reserved.

关键词： Edge computing

来源：评论

学校读者我要写书评

暂无评论

Emergence of 6-particle "hexciton" states in WS2 and MoSe2 monolayers

arXiv

引用

arXiv 2023年

作者： Choi, J. Li, J. Van Tuan, D. Dery, H. Crooker, Scott A. National High Magnetic Field Laboratory Los AlamosNM87545 United States Advanced Instrumentation Institute Korea Research Institute of Standards and Science Daejeon34113 Korea Republic of Wuhan National High Magnetic Field Center School of Physics Huazhong University of Science and Technology Hubei430074 China Department of Electrical and Computer Engineering University of Rochester RochesterNY14627 United States Department of Physics and Astronomy University of Rochester RochesterNY14627 United States

When doped with a high density of mobile charge carriers, monolayer transition-metal dichalcogenide (TMD) semiconductors can host new types of composite many-particle exciton states that do not exist in conventional semiconductors. Such multi-particle bound states arise when a photoexcited electron-hole pair couples to not just a single Fermi sea that is quantum-mechanically distinguishable (as for the case of conventional charged excitons or trions), but rather couples simultaneously to multiple Fermi seas, each having distinct spin and valley quantum numbers. Composite six-particle "hexciton" states were recently identified in electron-doped WSe2 monolayers, but under suitable conditions they should also form in all other members of the monolayer TMD family. Here we present spectroscopic evidence demonstrating the emergence of many-body hexcitons in charge-tunable WS2 monolayers (at the A-exciton) and MoSe2 monolayers (at the B-exciton). The roles of distinguishability and carrier screening on the stability of hexcitons are discussed. © 2023, CC BY.

关键词： Monolayers

来源：评论

学校读者我要写书评

暂无评论

Pushing AI to wireless network edge: An overview on integrated sensing, communication, and computation towards 6G

arXiv

引用

arXiv 2022年

作者： Zhu, Guangxu Lyu, Zhonghao Jiao, Xiang Liu, Peixi Chen, Mingzhe Xu, Jie Cui, Shuguang Zhang, Ping Shenzhen Research Institute of Big Data Shenzhen518172 China Shenzhen518172 China State Key Laboratory of Advanced Optical Communication Systems and Networks School of Electronics Peking University Beijing100871 China Department of Electrical and Computer Engineering Institute for Data Science and Computing University of Miami Coral Gables33146 United States State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing100876 China Peng Cheng Laboratory Shenzhen518066 China

Pushing artificial intelligence (AI) from central cloud to network edge has reached board consensus in both industry and academia for materializing the vision of artificial intelligence of things (AIoT) in the sixth-generation (6G) era. This gives rise to an emerging research area known as edge intelligence, which concerns the distillation of human-like intelligence from the huge amount of data scattered at wireless network edge. In general, realizing edge intelligence corresponds to the process of sensing, communication, and computation, which are coupled ingredients for data generation, exchanging, and processing, respectively. However, conventional wireless networks design the sensing, communication, and computation separately in a task-agnostic manner, which encounters difficulties in accommodating the stringent demands of ultra-low latency, ultra-high reliability, and high capacity in emerging AI applications such as auto-driving. This thus prompts a new design paradigm of seamless integrated sensing, communication, and computation (ISCC) in a task-oriented manner, which comprehensively accounts for the use of the data in the downstream AI applications. In view of its growing interest, this article provides a timely overview of ISCC for edge intelligence by introducing its basic concept, design challenges, and enabling techniques, surveying the state-of-the-art development, and shedding light on the road ahead. Copyright © 2022, The Authors. All rights reserved.

关键词： Artificial intelligence

来源：评论

学校读者我要写书评

暂无评论

Transition Metal-Vacancy Point Defects in Zinc Oxide as Deep-Level Spin Qubits

arXiv

引用

arXiv 2025年

作者： Zhang, Shimin Park, Taejoon Perez, Erik Li, Kejun Wang, Xingyi Wang, Yanyong Vega Bazantes, Jorge D. Zhang, Ruiqi Sun, Jianwei Fu, Kai-Mei C. Seo, Hosung Ping, Yuan Department of Materials Science and Engineering University of Wisconsin-Madison 53706 United States SKKU Advanced Institute of Nanotechnology Sungkyunkwan University Gyeonggi Suwon16419 Korea Republic of Department of Energy Systems Research Department of Physics Ajou University Gyeonggi Suwon16499 Korea Republic of Department of Physics University of California Santa CruzCA95064 United States Department of Electrical and Computer Engineering University of Washington SeattleWA98195 United States School of Science & Engineering Tulane University 6823 St Charles Ave New OrleansLA70118 United States Department of Physics University of Washington SeattleWA98195 United States Physical Sciences Division Pacific Northwest National Laboratory RichlandWA99352 United States Department of Quantum Information Engineering Sungkyunkwan University Gyeonggi Suwon16419 Korea Republic of Center for Quantum Information Korea Institute of Science and Technology Seoul02792 Korea Republic of Department of Physics University of Wisconsin-Madison 53706 United States Department of Chemistry University of Wisconsin-Madison 53706 United States

Wide band gap oxides are promising host materials for spin defect qubits, offering unique advantages such as a dilute nuclear spin environment. Zinc oxide (ZnO), in particular, can achieve exceptional high purity, which enables long spin coherence time. In this work, we theoretically search for deep-level point defects in ZnO with optimal physical properties for optically-addressable spin qubits. Using first-principles calculations, we predict the Molybdenum-vacancy complex defect (MoZnvO)2+ in ZnO to own promising spin and optical properties, including spin-triplet ground state, optical transition in the visible to near-infrared range with high quantum yield, allowed intersystem crossings with a sizable optically-detected magnetic resonance contrast, and long spin T2 and T∗2. Notably, we find the Huang-Rhys factor of the defect to be around 5, which is significantly smaller than the typical range of 10-30 for most known defects in ZnO. Furthermore, we compare the spin decoherence driven by the nuclear spin bath and paramagnetic impurity baths. We find that the paramagnetic impurities are very effective in causing spin decoherence even with very low concentrations, implying that they can likely dominate the spin decoherence in ZnO even after isotopic purification. Using the computed excited-state energies and kinetic rates as inputs, we predict the ODMR contrast and propose a new protocol for spin qubit initialization and readout, which could be generalized to other systems with forbidden axial intersystem crossings. © 2025, CC BY.

关键词： Zinc oxide

来源：评论

学校读者我要写书评

暂无评论

Double-Free-Layer Magnetic Tunnel Junctions for Probabilistic Bits

引用

Physical Review Applied 2021年第4期15卷 044049-044049页

作者： Kerem Y. Camsari Mustafa Mert Torunbalci William A. Borders Hideo Ohno Shunsuke Fukami Department of Electrical and Computer Engineering University of California Santa Barbara California 93106 USA Birck Nanotechnology Center Purdue University West Lafayette Indiana 47907 USA Laboratory for Nanoelectronics and Spintronics Research Institute of Electrical Communication Tohoku University Japan Center for Spintronics Research Network Tohoku University Japan Center for Science and Innovation in Spintronics Tohoku University Japan WPI Advanced Institute for Materials Research Tohoku University Japan Center for Innovative Integrated Electronic Systems Tohoku University Japan

Naturally random devices that exploit ambient thermal noise have recently attracted attention as hardware primitives for accelerating probabilistic computing applications. One such approach is to use a low barrier nanomagnet as the free layer of a magnetic tunnel junction (MTJ), the magnetic fluctuations of which are converted to resistance fluctuations in the presence of a stable fixed layer. Here, we propose and theoretically analyze a MTJ with no fixed layers but two free layers that are circularly shaped disk magnets. We use an experimentally benchmarked model that accounts for finite-temperature magnetization dynamics, bias-dependent charge, and spin-polarized currents as well as the dipolar coupling between the free layers. We obtain analytical results for statistical averages of fluctuations that are in good agreement with the numerical model. We find that the free layers with low diameters fluctuate to randomize the resistance of the MTJ in an approximately bias-independent manner. We show how such MTJs can be used to build a binary stochastic neuron (or a p-bit) in hardware. Unlike earlier stochastic MTJs that need to operate at a specific bias point to produce random fluctuations, the proposed design can be random for a wide range of bias values, independent of spin-transfer-torque pinning. Moreover, in the absence of a carefully optimized stabled fixed layer, the symmetric double-free-layer stack can be manufactured using present-day magnetoresistive random-access memory (MRAM) technology by minimal changes to the fabrication process. Such devices can be used as hardware accelerators in energy-efficient computing schemes that require a large throughput of tunably random bits.

关键词： Spintronics Superparamagnetism Magnetic tunnel junctions

来源：评论

学校读者我要写书评

暂无评论

How to Build a Quantum Supercomputer: Scaling Challenges and Opportunities

arXiv

引用

arXiv 2024年

作者： Mohseni, Masoud Scherer, Artur Johnson, K. Grace Wertheim, Oded Otten, Matthew Aadit, Navid Anjum Bresniker, Kirk M. Camsari, Kerem Y. Chapman, Barbara Chatterjee, Soumitra Dagnew, Gebremedhin A. Esposito, Aniello Fahim, Farah Fiorentino, Marco Khalid, Abdullah Kong, Xiangzhou Kulchytskyy, Bohdan Li, Ruoyu Lott, P. Aaron Markov, Igor L. McDermott, Robert F. Pedretti, Giacomo Gajjar, Archit Silva, Allyson Sorebo, John Spentzouris, Panagiotis Steiner, Ziv Torosov, Boyan Venturelli, Davide Visser, Robert J. Webb, Zak Zhan, Xin Cohen, Yonatan Ronagh, Pooya Ho, Alan Beausoleil, Raymond G. Martinis, John M. Hewlett Packard Labs CA United States BC Canada Quantum Machines Israel Department of Physics University of Wisconsin–Madison WI United States Department of Electrical and Computer Engineering University of California Santa BarbaraCA United States Hewlett Packard Enterprise TX United States Fermi National Accelerator Laboratory IL United States Applied Materials CA United States USRA Research Institute for Advanced Computer Science CA United States NASA Ames Research Center CA United States Synopsys CA United States Qolab CA United States Institute for Quantum Computing University of Waterloo ON Canada Department of Physics & Astronomy University of Waterloo ON Canada Perimeter Institute for Theoretical Physics ON Canada

In the span of four decades, quantum computation has evolved from an intellectual curiosity to a potentially realizable technology. Today, small-scale demonstrations have become possible for quantum algorithmic primitives on hundreds of physical qubits and proof-of-principle error-correction procedures on a single logical qubit. Nevertheless, despite significant progress and excitement, the detailed path toward a full-stack scalable quantum computing technology is largely unknown. There are significant outstanding quantum hardware, fabrication, software architecture, and algorithmic challenges that are either unresolved or overlooked. These issues could seriously undermine the arrival of utility-scale quantum computers for the foreseeable future. Here, we provide a comprehensive review of these scaling challenges. We show how the road to scaling could be paved by adopting existing semiconductor technology to build much higher-quality qubits, employing system engineering approaches, and performing distributed quantum computation within heterogeneous high-performance computing infrastructures. These opportunities for research and development could unlock certain promising applications, in particular, efficient quantum simulation and learning/modeling quantum data generated by natural or engineered quantum systems. In order to estimate the true cost of such promises, we provide a detailed resource and sensitivity analysis for classically hard quantum chemistry calculations on surface-code error-corrected quantum computers given current, target, and desired hardware specifications based on superconducting qubits, accounting for a realistic distribution of errors. We show orders of magnitude enhancement in performance could be obtained by a combination of quantum hardware and algorithmic improvements. Furthermore, we argue that, to tackle today’s industry-scale classical optimization and machine learning problems in a cost-effective manner, distributed quantum-assisted p

关键词： Qubits

来源：评论

学校读者我要写书评

暂无评论

Scattering-free plasmonic Brewster effect via metasurfaces

arXiv

引用

arXiv 2024年

作者： Zhang, Xinyan Cui, Xingshuo Cai, Tong Cai, Weiqi Low, Tony Chen, Hongsheng Lin, Xiao Interdisciplinary Center for Quantum Information State Key Laboratory of Extreme Photonics and Instrumentation College of Information Science and Electronic Engineering Zhejiang University Hangzhou310027 China International Joint Innovation Center The Electromagnetics Academy at Zhejiang University Zhejiang University Haining314400 China Air and Missile Defense College Air Force Engineering University Xi’an710051 China AVIC Research Institute for Special Structures of Aeronautical Composites Jinan250023 China Department of Electrical and Computer Engineering University of Minnesota MinneapolisMN55455 United States Key Lab. of Advanced Micro/Nano Electronic Devices & Smart Systems of Zhejiang Jinhua Institute of Zhejiang University Zhejiang University Jinhua321099 China Shaoxing Institute of Zhejiang University Zhejiang University Shaoxing312000 China

The Brewster effect, dating back to the pioneering work of Sir David Brewster in 1815, offers a crucial route to achieve 100% energy conversion between the incident and transmitted propagating waves at an optical interface and is of fundamental importance to many practical applications, such as polarization filtering, beam steering, and optical broadband angular selectivity. However, whether the Brewster effect of surface waves can be implemented without the involvement of negative-permittivity or negative-permeability materials remains elusive. This is due to the formidable challenge to fully suppress both the parasitic scattering into propagating waves and the reflection into surface waves under the incidence of surface waves. Here, we reveal a feasible route to achieve scattering-free plasmonic Brewster effect via isotropic metasurfaces, along with the usage of positive-permittivity and positive-permeability metamaterials with both anisotropic and magnetic responses. In essence, the anisotropic response of metamaterials is judiciously designed to fully suppress the parasitic scattering into propagating waves, while the magnetic response of metamaterials facilitates the full suppression of the reflection into surface waves supported by metasurfaces. Moreover, we find that this plasmonic Brewster effect via metasurfaces can be further engineered to occur for arbitrary incident angles, giving rise to the exotic phenomenon of all-angle scattering-free plasmonic Brewster effect. © 2024, CC BY.

关键词： Surface waves

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：