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2018 Conference on Optoelectronic Devices and Integration, OEDI 2018, part of International Photonics and Optoelectronics Meeting, POEM 2018

作者： An, Shaohua Zhu, Qingming Li, Jingchi Pang, Hongxin Su, Yikai State Key Laboratory of Advanced Optical Communication Systems and Networks Department of Electronic Engineering Shanghai Jiao Tong University 800 Dongchuan Rd Shanghai200240 China

We experimentally demonstrate a 102-Gb/s DMT signal transmission over 105-km single-span SMF in an IM-DD system. This work reports the highest single-wavelength and singlepolarization net data rate × single span ... 详细信息

ISBN: (纸本)9781943580514

关键词： Distributed feedback lasers Fast Fourier transforms optical signals Orthogonal frequency division multiplexing Phase modulation Signal transmission

Multipartite entanglement of billions of motional atoms heralded by single photon

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arXiv 2020年

作者： Li, Hang Dou, Jian-Peng Pang, Xiao-Ling Zhang, Chao-Ni Yan, Zeng-Quan Yang, Tian-Huai Gao, Jun Li, Jia-Ming Jin, Xian-Min School of Physics and Astronomy State Key Laboratory of Advanced Optical Communication Systems and Networks Shanghai Jiao Tong University Shanghai200240 China CAS Center for Excellence Synergetic Innovation Center in Quantum Information and Quantum Physics University of Science and Technology of China Hefei Anhui230026 China School of Physics and Astronomy Shanghai Jiao Tong University Shanghai200240 China

Quantum entanglement is of central importance to quantum computing, quantum metrology, quantum information as well as the nature of quantum physics. Quantum theory does not prevent entanglement from being created and observed in macroscopic physical systems, in reality however, the accessible scale of entanglement is still very limited due to decoherence effects. Recently, entanglement has been observed among atoms from thousands to millions level in extremely low-temperature and well-isolated systems. Here, we create multipartite entanglement of billions of motional atoms in a quantum memory at room temperature, and certify the genuine entanglement via M-separability witness associated with photon statistics. The information contained in a single photon is found strongly correlated with the excitation shared by the motional atoms, which intrinsically address the large system and therefore stimulate the multipartite entanglement. Remarkably, our heralded and quantum memory built-in entanglement generation allows us to directly observe the dynamic evolution of entanglement depth and further to reveal the effects of decoherence. Our results verify the existence of genuine multipartite entanglement among billions of motional atoms at ambient condition, significantly extending the boundary of the accessible scale of entanglement. Besides probing the quantum-to-classical transition in an entirely new realm, the developed abilities of manipulating such a large-scale entanglement may enhance a wide spectrum of applications for emerging quantum technologies. Copyright © 2020, The Authors. All rights reserved.

关键词： Atoms

White Beam Lasing from a Hybrid Microcavity with Slab-Capillary Mode Coupling

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Physical Review Applied 2019年第6期11卷 064055-064055页

作者： Hai-Lang Dai Cheng Yin Zhi-yuan Xiao Zhuang-Qi Cao Xian-Feng Chen The State Key Laboratory on Fiber Optic Local Area Communication Networks and Advanced Optical Communication Systems School of Physics and Astronomy Shanghai Jiao Tong University Shanghai 200240 China Collaborative Innovation Center of IFSA (CICIFSA) Shanghai Jiao Tong University Shanghai 200240 China Jiangsu Key Laboratory of Power Transmission and Distribution Equipment Technology Hohai University Changzhou 213022 China

We report a hybrid multichannel metal-cladded slab-capillary microcavity, which supports simultaneous red, green, and blue lasing from an individual microcavity at room temperature. White and tunable lasing over the full range of visible colors is achieved through controlled injection of different dye solutions into the metal-cladded capillaries of the microcavity. The results show that RGB lasing beams with a line width of approximately 1 nm are observed from the metal-cladded slab-capillary microcavity. The experimental observations show the realization of white light and lasing simultaneously in a single hybrid microcavity. Moreover, the improvement in the laser structure enables the elimination of background noise. Our work describes a simplification in fabricating microlasers with dynamically color-controllable emissions and provides an important route toward the potential of realizing a microlaser device generating both white and full color light directly from a single monolithic structure.

关键词： Dye lasers Integrated optics Laser-system design Microcavity & microdisk lasers Optoelectronics Photonics Tunable lasers Waveguides

Ultra-high range resolution demonstration of a photonics-based microwave radar using a high-repetition-rate mode-locked fiber laser

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Chinese Optics Letters 2018年第6期16卷 88-92页

作者： Shaofu Xu Weiwen Zou Guang Yang Jianping Chen State Key Laboratory of Advanced Optical Communication Systems and Networks Shanghai Institute for Advanced Communication and Data Science Department of Electronic Engineering Shanghai Jiao Tong University Shanghai 200240 China

We experimentally demonstrate the ultra-high range resolution of a photonics-based microwave radar using a high repetition rate actively mode-locked laser（AMLL）. The transmitted signal and sampling clock in the radar originate from the same AMLL to achieve a large instantaneous bandwidth. A Ka band linearly frequency modulated signal with a bandwidth up to 8 GHz is successfully generated and processed with the electro-optical upconversion and direct photonic sampling. The minor lobe suppression（MLS） algorithm is adopted to enhance the dynamic range at a cost of the range resolution. Two-target discrimination with the MLS algorithm proves the range resolution reaches 2.8 cm. The AMLL-based microwave-photonics radar shows promising applications in high-resolution imaging radars having the features of high-frequency band and large bandwidth.

关键词： Ultra-high range resolution demonstration of a photonics-based microwave radar using a high-repetition-rate mode-locked fiber laser

Up to 168-Gb/s PAM-4 direct detection transmission with silicon travelling wave Mach-Zehnder modulator

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arXiv 2018年

作者： Yang, Fan Zhu, Yixiao Zhang, Lei Ruan, Xiaoke Li, Yanping Zhang, Fan State Key Laboratory of Advanced Optical Communication System and Networks Peking University Beijing China

Based on a silicon travelling wave Mach-Zehnder modulator, we demonstrate record 168Gb/s (84Gbaud) and 160Gb/s (80Gbaud) PAM-4 direct detection transmission over 1km and 2km SSMF, respectively, with bit error rates be... 详细信息

关键词： Light modulators

Pseudo pilot-aided OFDM system with high spectral efficiency for high performance coaxial transmission

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Science China(Information Sciences) 2017年第6期60卷 191-199页

作者： Yue LIU Chuanchuan YANG Hongbin LI State Key Laboratory of Advanced Optical Communication Systems and Networks School of Electronics Engineering and Computer Science Peking University

High performance network over coax(HINOC) has become next-generation broadcasting network(NGB) industry standard of China, as well as International Telecommunication Union(ITU) telecommunication standard, which adopts orthogonal frequency division multiplexing(OFDM) technique and high order modulation formats. As is known, in OFDM system, phase noise destroys the orthogonality of the subcarriers and degrades the performance of the system especially when the data are transmitted in high order modulation formats. In this paper, we propose a high spectral efficiency OFDM system utilizing a novel and almost blind phase noise compensation method mainly used for high performance coaxial transmission. In our system, some subcarriers, which remain to transmit unknown useful data in lower order modulation formats, are selected as pseudo pilots instead of pilots to suppress phase noise effectively and high spectral efficiency can be achieved with the aid of puncturing mechanisms. Simulation results show that the proposed pseudo pilot-aided OFDM system can achieve the performance of the pilot-aided counterpart yet acquiring higher spectral efficiency.

关键词： orthogonal frequency division multiplexing(OFDM) high performance network over coax(HINOC) phase noise pseudo pilots broadcasting

Observing movement of Dirac cones from single-photon dynamics

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arXiv 2020年

作者： Lu, Yong-Heng Wang, Yao Chang, Yi-Jun Li, Zhan-Ming Cui, Wen-Hao Gao, Jun Zhou, Wen-Hao Zheng, Hang Jin, Xian-Min School of Physics and Astronomy State Key Laboratory of Advanced Optical Communication Systems and Networks Shanghai Jiao Tong University Shanghai200240 China CAS Center for Excellence Synergetic Innovation Center in Quantum Information and Quantum Physics University of Science and Technology of China HefeiAnhui230026 China Laboratory of Artificial Structures and Quantum Control Ministry of Education School of Physics and Astronomy Shanghai Jiao Tong University Shanghai200240 China

Graphene with honeycomb structure, being critically important in understanding physics of matter, exhibits exceptionally unusual half-integer quantum Hall effect and unconventional electronic spectrum with quantum relativistic phenomena. Particularly, graphene-like structure can be used for realizing topological insulator which inspires an intrinsic topological protection mechanism with strong immunity for maintaining coherence of quantum information. These various peculiar physics arise from the unique properties of Dirac cones which show high hole degeneracy, massless charge carriers and linear intersection of bands. Experimental observation of Dirac cones conventionally focuses on the energy-momentum space with bulk measurement. Recently, the wave function and band structure have been mapped into the real-space in photonic system, and made flexible control possible. Here, we demonstrate a direct observation of the movement of Dirac cones from single-photon dynamics in photonic graphene under different biaxial strains. Sharing the same spirit of wave-particle nature in quantum mechanics, we identify the movement of Dirac cones by dynamically detecting the edge modes and extracting the diffusing distance of the packets with accumulation and statistics on individual single-particle registrations. Our results of observing movement of Dirac cones from single-photon dynamics, together with the method of direct observation in real space by mapping the band structure defined in momentum space, pave the way to understand a variety of artificial structures in quantum regime. Copyright © 2020, The Authors. All rights reserved.

关键词： Graphene

256 MHz, 1 W 780 nm femtosecond fiber laser for two-photon microscopy

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256 MHz, 1 W 780 nm femtosecond fiber laser for two-photon m...

Conference on Lasers and Electro-Optics/Pacific Rim, CLEOPR 2018

作者： Yang, Wan Wu, Danlei Liu, Guanyu Chen, Bingying Feng, Lishuang Zhang, Zhigang Wang, Aimin State Key Laboratory of Advanced Optical Communication System and Networks School of Electronics Engineering and Computer Science Peking University Beijing100871 China Key Lab Precision Opto-mechatronics Technology Ministry of Education School of Instrumentation Science and Optoelectronics Engineering Beihang University Beijing100191 China

A robust 780 nm femtosecond fiber laser was demonstrated with 191 fs pulse width, 256 MHz repetition rate and 1 W average power. It is ideal for two-photon microscopic imaging. © OSA 2018

ISBN: (纸本)9781943580453

A robust 780 nm femtosecond fiber laser was demonstrated with 191 fs pulse width, 256 MHz repetition rate and 1 W average power. It is ideal for two-photon microscopic imaging. © OSA 2018

关键词： Pulse repetition rate

Optimizing network resource allocation with graph pointer neural network in large-scale AI systems

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Digital communications and networks 2024年

作者： Peiying Zhang Yilin Li Athanasios V. Vasilakos Konstantin Igorevich Kostromitin Jianyong Zhang Mohsen Guizani Qingdao Institute of Software College of Computer Science and Technology China University of Petroleum (East China) Qingdao 266580 China State Key Laboratory of Integrated Services Networks Xidian University Xi'an 710071 China Key Laboratory of Computing Power Network and Information Security Ministry of Education Shandong Computer Science Center (National Supercomputer Center in Jinan) Qilu University of Technology (Shandong Academy of Sciences) Jinan 250013 China Department of Networks and Communications College of Computer Science and Information Technology Imam Abdulrahman Bin Faisal University P.O. Box 1982 Dammam 31441 Saudi Arabia Department of Physics of Nanoscale Systems South Ural State University Chelyabinsk 454080 the Russian Federation Institute of Lightwave Technology Beijing Jiaotong University Beijing 100044 China Key Lab of All Optical Network and Advanced Telecommunication of EMC Institute of Lightwave Technology Beijing Jiaotong University Beijing 100044 China Machine Learning Department Mohamed Bin Zayed University of Artificial Intelligence (MBZUAI) Abu Dhabi 999041 United Arab Emirates

For increasingly complex communication demands of large-scale AI communication systems, the Space-Air-Ground Integrated Network (SAGIN) better caters to demands but also raises concerns about resource scarcity and diversity. This paper innovatively combines Graph Pointer Neural networks (GPNN) and Reinforcement Learning (RL) to enhance resource allocation efficiency. The method leverages the advantages of GPNN in handling graph data and RL in optimizing decisions in dynamic environments. It also targets the optimization goal of maximizing resource allocation while minimizing deployment latency. This paper begins by modeling SAGIN and elucidating the SAGIN logical architecture based on Software-defined Networking (SDN). Subsequently, it introduces an SFC deployment algorithm aimed at joint optimization of resource allocation and latency. The algorithm leverages GPNN and RL to deploy virtual nodes and links, with the goal of optimizing resource allocation and deployment latency. Experiment findings conclusively demonstrate that the efficacy of proposed algorithm in effectively weighing limited heterogeneous resources and minimum mapping delay. Notably, when compared to three other SFC mapping algorithms MLRL, NFVdeep, and RL, the proposed algorithm consistently outperforms them, with an average improvement of 10.17% in long-term average reward/cost, 11.21% in link resource utilization ratio, 15.34% in node resource utilization ratio, and 16.38% in acceptance ratio.

关键词： Space-air-ground integrated network Topological structure Reinforcement learning Service function chain Graph pointer neural network

Intelligent metasurface imager and recognizer

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arXiv 2019年

作者： Li, Lianlin Shuang, Ya Ma, Qian Li, Haoyang Zhao, Hanting Wei, Menglin Liu, Che Hao, Chenglong Qiu, Cheng-Wei Cui, Tie Jun State Key Laboratory of Advanced Optical Communication Systems and Networks Department of Electronics Peking University Beijing100871 China State Key Laboratory of Millimeter Waves Southeast University Nanjing210096 China Department of Electrical and Computer Engineering National University of Singapore 4 Engineering Drive 3 Singapore117583 Singapore

It is ever-increasingly demanded to remotely monitor people in daily life using radio-frequency probing signals. However, 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 tag. To accomplish the complicated successive tasks using a single device in real time, we propose a smart metasurface imager and recognizer simultaneously, empowered by a network of artificial neural networks (ANNs) for adaptively controlling data flow. Here, three ANNs are employed in an integrated hierarchy: transforming measured microwave data into images of whole human body;classifying the specifically designated spots (hand and chest) within the whole image;and recognizing human hand signs instantly at Wi-Fi frequency of 2.4 GHz. Instantaneous in-situ imaging of full scene and adaptive recognition of hand signs and vital signs of multiple non-cooperative people have been experimentally demonstrated. We also show that the proposed intelligent metasurface system work well even when it is passively excited by stray Wi-Fi signals that ubiquitously exist in our daily lives. The reported strategy could open a new avenue for future smart cities, smart homes, human-device interactive interfaces, healthy monitoring, and safety screening free of visual privacy issues. Copyright © 2019, The Authors. All rights reserved.

关键词： Neural networks