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Adiabatic Passage Based on the Calcium Active optical Clock

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Chinese Physics Letters 2010年第7期27卷 105-107页

作者：解晓鹏庄伟陈景标 Institute of Quantum Electronics and State Key Laboratory of Advanced Optical Communication System & Network School of Electronics Engineering & Computer Science Peking University Beijing 100871

We propose a new application of the optical adiabatic passage effect for the excitation of a thermal atomic beam, which will be used in the calcium active optical clock to produce population inversion. A comparison between the optical adiabatic passage effect and the Rabi π pulse is investigated, 99% of the calcium atoms in the atomic beam that has a wide velocity distribution will be excited to the upper state for population inversion using the adiabatic passage, while 76% at most will be excited to the excited state using the π pulse with suitable parameters.

关键词： ATOMIC beams optical properties NUCLEAR excitation MATRIX inversion CALCIUM PARTICLE beams

A Potassium Atom Four-Level Active optical Clock Scheme

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Chinese Physics Letters 2013年第4期30卷 34-37页

作者： ZHANG Sheng-Nan WANG Yan-Fei ZHANG Tong-Gang ZHUANG Wei CHEN Jing-Biao Institute of Quantum Electronics and state key laboratory of advanced optical communication and System Network School of Electronics Engineering and Computer SciencePeking UniversityBeijing 100871

We present an active optical clock scheme with a four-level quantum potassium *** calculate the population probabilities of each state using the density *** the steady state,ρ33 andρ55 are equal to 8.3%and 3.5%,respectively,and the population inversion between the 5S1/2 and 4P3/2 states is built up in the thermal potassium cell with a 404.7 nm pumping *** to the mechanism of the active optical clock,under the action of the 404.7 nm pumping laser,the scheme can output a 1252.2 nm quantum-limited-linewidth laser,which can be directly used as an active optical frequency standard.

关键词： pumping potassium quantum

An Eavesdropping Detecting Approach Based on Mode-Mode Correlation

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Chinese Physics Letters 2005年第11期22卷 2748-2750页

作者：熊锦曾贵华周南润 The state key laboratory on Fiber-Optic Local Area Networks and advanced optical communication Systems Department of Electronic Engineering Shanghai Jiaotong University Shanghai 200240

We find that second-order coherence as well as a Hanbury-Brown-Twiss intensity interferometer may provide an optimal approach for eavesdropping detection in the quantum key distribution based on two-mode squeezed vacuum states. With this approach, eavesdropping can be easily detected without sacrificing extra secret bits as the test key. In addition, the efficiency of the quantum key distribution protocol is enhanced greatly.

关键词： VARIABLES

Lasing Frequency Up-Conversion by Using Thermal Population

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Journal of Shanghai Jiaotong university(Science) 2019年第5期24卷 579-583页

作者： NKONDE Sampa JIANG Chun state key laboratory of advanced optical communication Systems and Networks Department of Electronic EngineeringShanghai Jiao Tong University

We theoretically demonstrate a model which can be used to analyze frequency up-conversion of a laser wavelength by using thermal population. The proposed model uses a rate equation model of ytterbium-doped fiber with thermal population effect. The rate and power propagation equations are set up and numerically analyzed to elucidate the dependence of frequency up-conversion efficiency and thermal-optical conversion efficiency on ambient thermal power. The analytical techniques and numerical results show that using pump laser at 1 000 nm,the wavelength can be converted into 900 nm with an up-conversion quantum efficiency of about 99.97% and a cooling efficiency of about 11.1%. This theoretical model is a promising candidate for vast applications in energyefficient laser and energy-utilizing field.

关键词： fiber laser frequency up-conversion thermal population lasing

A novel polarization channel drop filter based on two-dimensional photonic crystals

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Chinese Optics Letters 2010年第8期8卷 749-752页

作者：任宏亮覃亚丽刘恺吴哲夫胡卫生姜淳金耀辉 Institute of Fiber Optic communication and Information Engineering College of Information EngineeringZhejiang University of Technology state key laboratory of advanced optical communication Systems and Networks Shanghai Jiao Tong University

A novel polarization channel drop filter （PCDF） based on two-dimensional （2D） photonic crystals （PCs） is presented. It consists of two line defect waveguides and two point defect micro-cavities. In the line-defect waveguides, the transverse-electric （TE） and transverse-magnetic （TM） polarization lights are guided using photonic band-gap and total internal reflection effect, respectively. The light at the resonant frequency for TE polarization can be transferred from one waveguide to the other using the proposed system. Compared with the existing four-port PCDF based on PCs, the three-port structure can realize a multi-channel wavelength system of PCDF more easily and can be an essential device in future polarization wavelength division multiplexing （PWDM） systems.

关键词： Defects Drops Multiplexing Multiplexing equipment Natural frequencies optical waveguides Photonic band gap Point defects Polarization Refractive index Two dimensional Waveguides

Study of the photonic crystal waveguide based on 2D compound lattice structure

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Optoelectronics Letters 2009年第5期5卷 321-323页

作者：吴朝军李艳萍王子宇 state key laboratory on advanced optical communication Systems and Networks School of Electronics Engineering and Computer Science Peking University

By employing 2D plane wave expansion (PWE) and finite difference time domain (FDTD) methods,a photonic crystal waveguide (PCW) based on the compound square lattice structure is presented. Band-gap can be observed for TM polarization and compared with the simple lattice structure based on the same material,the band-gap is increased by 62.7%. Byoptimizing the parameters we get the PCW with the propagation only near the wavelength of 1.55 μm and a flat group indexcurve in a wide wavelength range of 40 nm. And the group velocity dispersion compensation can be realized by thestructure optimization. The results provide a reference for the study and application of photonic crystal waveguide based on the compound lattice structure.

关键词：二维光子晶体光子晶体波导晶格结构基础复合时域有限差分法平面波展开波长范围

Correction of timing mismatches between two channels for photonic analog-to-digital converters

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Optoelectronics Letters 2018年第6期14卷 429-433页

作者： ZHANG He WU Gui-ling WANG Cheng CHEN Jian-ping state key laboratory of advanced optical communication Systems and Networks Department of Electronic Engineering Shanghai Jiao Tong University

This paper presents a scheme to identify and compensate the timing mismatches between two channels for tipme interleaved photonic analog-to-digital converters(TIPADCs). The impact of electro-optic sampling is removed by preprocessing firstly. Then a calibration method combining chopping processing and a Hilbert transform is proposed to identify the timing mismatches, which can be further compensated by using various mature compensation algorithms. The principle of the proposed method is derived theoretically. The performance of the scheme is analyzed by simulation. The results show that the harmonic induced by timing mismatches can be suppressed by more than 30 dB using the proposed correction scheme.

关键词： Correction photonic analog-to-digital converters timing

Incident Light Influence on the Transmission of Coupled Ring Resonators

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Tsinghua Science and Technology 2010年第2期15卷 198-201页

作者：孙月徐连宇彭超李正斌 state key laboratory on advanced optical communication Systems & Networks School of Electronic Engineering and Computer Science Peking University

The transmission matrix method is used to analyze the influence of incident light on coupled resonators. Two different types of incident light on the same coupled resonator geometry are shown to lead to different system transmission features. The EIT-like phenomenon occurs in the type I case with the transmission being symmetric around the zero-single-pass-phase-shift frequency. In the type Ⅱcase the resonant frequency has a blue shift corresponding to the increasing coupling strength between the two ring resonators. Also, the critical-coupling-like condition exists in the type Ⅱconfiguration to maintain the zero-single pass-phase-shift frequency. The incident light, as well as the geometry, partially determine the mode interference in the coupled ring resonator system.

关键词： coupled ring resonator mode excitation resonance frequency shift

Artificial intelligence-driven autonomous optical networks: 3S architecture and key technologies

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Science China(Information Sciences) 2020年第6期63卷 7-30页

作者： Yuefeng JI Rentao GU Zeyuan YANG Jin LI Hui LI Min ZHANG state key laboratory of Information Photonics and optical communications School of Information and Communication Engineering Beijing University of Posts and Telecommunications state key laboratory of Information Photonics and optical communications Institute of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications

In the optical networks, the dynamicity, the complexity and the heterogeneity have dramatically increased owing to the deployment of advanced coherent techniques, and the optical cross-connect technologies and diverse network infrastructures pose great challenges in the optical network management and maintenance for the network operators. In this review, we propose a "3 S" architecture for AI-driven autonomous optical network, which can aid the optical networks operated in "self-aware" of network status, "self-adaptive" of network control, and "self-managed" of network operations. To support these functions, a number of artificial intelligence(AI)-driven techniques have been investigated to improve the flexibility and the reliability from the device aspect to network aspect. Adaptative erbium-doped fiber amplifier(EDFA) controlling is an example for the device aspect, which provides a power self-adaptive capability according to the network *** the link aspect, adaptive fiber nonlinearity compensation, optical monitoring performance and quality of transmission estimation are developed to monitor and alleviate the link-dependent signal impairments in an automatic way. From the network aspect, traffic prediction and network state analysis methods provide the self-awareness, while automatic resource allocation and network fault management powered by AI enhance the self-adaptiveness and self-management capabilities. Benefit from the sufficient network management data,powerful data-mining capability and matured computation units, these AI techniques have great potentials to provide autonomous features for optical networks, including the network resource scheduling and the network customization.

关键词： artificial intelligence optical networks self-aware self-adaptive self-managed