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Robust Optical Frequency Comb Generation Based on Optical Parametric Oscillation in a High-index Micro-ring Resonator

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Robust Optical Frequency Comb Generation Based on Optical Pa...

Terabit FSO communication based on a soliton microcomb

全国第17次光纤通信暨第18届集成光学学术会议

作者： Weiqiang Wang Sai T.Chu brent e.little Yishan Wang Yuanshan Liu Wenfu Zhang Wei Zhao State Key Laboratory of Transient Optics and Photonics Xi'an Institute of Optics and Precision Mechanics Chinese Academy of Sciences

In this paper,we present an optical frequency comb（OFC）which is generated by the optical parametric oscillation（OPO）in an integrated CMOS-compatible high resonance factor（Q.45×106）nonlinear micro-ring *** pump is generated by self-oscillation in the main cavity（self-locked）and no self-termination is observed during our experiments which troubled external pump optical frequency combs *** our scheme,a more than 150nm bandwidth optical frequency comb is generated with mode spacing consistent to the free spectral range（FSR）of our micro-ring resonator（50GHz）.This robust OFC has potential applications in astronomy,microwave photonics,or telecommunications,etc.

关键词： Micro-ring resonator Optical parametric oscillation Optical frequency comb

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Photonics Research 2022年第12期10卷 2802-2808页

作者： WeN SHAO YANG WANG SHUAIWeI JIA ZHUANG XIe DUORUI GAO WeI WANG DONGQUAN ZHANG PeLXUAN LIAO brent elittle SAI TCHU WeI ZHAO WeNFU ZHANG WeIQIANG WANG XIAOPING XIe State Key Laboratory of Transient Optics and Photonics Xi’an Institute of Optics and Precision Mechanics(XIOPM)Chinese Academy of SciencesXi'an 710119China School of Future Technology University of Chinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China Department of Physics and Materials Science City University of Hong KongHong KongChina

Free-space optical(FSO)communication technology is a promising approach to establish a secure wireless link,which has the advantages of excellent directionality,large bandwidth,multiple services,low mass and less power requirements,and easy and fast *** the communication capacity is the perennial goal in both scientific and engineer *** this paper,we experimentally demonstrate a Tbit/s parallel FSO communication system using a soliton microcomb as a multiple wavelength laser *** communication terminals are installed in two buildings with a straight-line distance of~1 km.102 comb lines are modulated by10 Gbit/s differential phase-shift keying signals and demodulated using a delay-line *** the transmitted optical power is amplified to 19.8 dBm,42 optical channels have optical signal-to-noise ratios higher than 27 dB and bit error rates less than 1×10^(-9).Our experiment shows the feasibility of a wavelength-division multiplexing FSO communication system which suits the ultra-high-speed wireless transmission application scenarios in future satellite-based communications,disaster recovery,defense,last mile problems in networks and remote sensing,and so on.

关键词： communication FSO interferometer

Preface to the Special Issue on Semiconductor Optoelectronic Integrated Circuits

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Journal of Semiconductors 2021年第4期42卷 1-2页

作者： Wei Wang Lingjuan Zhao Dan Lu Jianping Yao Weiping Huang Yong Liu brent little Institute of Semiconductors Chinese Academy of SciencesBeijing 100083China School of electrical engineering and Computer Science University of OttawaOttawaOntarioCanada School of Information Science and engineering Shandong UniversityJinan 250100China University of electronic Science and Technology Chengdu 610054China QXP Technologies Inc. Xi’an 710117China

The past 20 years have witnessed the rapid growth of photonic integration circuits(PIC)technology,which has been warmly embraced by both academia and the *** by the advanced development in material growth,processing,and design capability,the PIC technology now covers multiple material platforms,including III–V(InP,GaAs),silicon,silica,lithium niobate on insulator(LNOI)polymer,*** integration level has evolved from a single functional device to thousands of components *** increase in the performance and the complexity of the PICs have become an energetic booster for communication and information technology.

关键词： integration lithium silica

Numerical modeling of the effects of roughness on flow and eddy formation in fractures

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Journal of Rock Mechanics and Geotechnical engineering 2017年第1期9卷 105-115页

作者： Scott Briggs Bryan W. Karney brent e. Sleep University of Toronto Toronto M5S 1A4 Canada

The effect of roughness on flow in fractures was investigated using lattice Boltzmann method(LBM).Simulations were conducted for both statistically generated hypothetical fractures and a natural dolomite fracture. The effect of increasing roughness on effective hydraulic aperture, Izbash and Forchheimer parameters with increasing Reynolds number(Re) ranging from 0.01 to 500 was examined. The growth of complex flow features, such as eddies arising near the fracture surface, was directly associated with changes in surface roughness. Rapid eddy growth above Re values of 1, followed by less rapid growth at higher Re values, suggested a three-zone nonlinear model for flow in rough fractures. This three-zone model, relating effective hydraulic conductivity to Re, was also found to be appropriate for the simulation of water flow in the natural dolomite fracture. Increasing fracture roughness led to greater eddy volumes and lower effective hydraulic conductivities for the same Re values.

关键词： Hydrogeology Fracture flow Fracture roughness Computational fluid dynamics Lattice Boltzmann method(LBM)

Tranexamic acid for major trauma patients in Ireland

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World Journal of emergency Medicine 2022年第1期13卷 11-17页

作者： Kieran Walsh Francis O’Keeff e Louise brent Biswadev Mitra National Trauma Research Institute the Alfred HospitalMelbourne 3004Australia Critical Care Research School of Public Health and Preventive MedicineMonash UniversityMelbourne 3004Australia emergency&Trauma Centre Alfred HealthMelbourne 3004Australia emergency Department Mater Misericordiae University HospitalDublin D07 R2WYIreland National Offi ce for Clinical Audit Ardilaun HouseDublin D02 VN51Ireland

BACKGROUND:The Clinical Randomisation of an Anti-fibrinolytic in Significant Hemorrhage-2(CRASH-2)is the largest randomized control trial(RCT)examining circulatory resuscitation for trauma patients to date and concluded a statistically significant reduction in all-cause mortality in patients administered tranexamic acid(TXA)within 3 hours of *** the publication of CRASH-2,significant geographical variance in the use of TXA for trauma patients *** study aims to assess TXA use for major trauma patients with hemorrhagic shock in Ireland after the publication of ***:A retrospective cohort study was conducted using data derived from the Trauma Audit and Research Network(TARN).All injured patients in Ireland between January 2013 and December 2018 who had evidence of hemorrhagic shock on presentation(as defined by systolic blood pressure[SBP]ere eligible for *** at hospital discharge was the primary ***:During the study period,a total of 234 patients met the inclusion *** injured patients presenting with hemorrhagic shock,133(56.8%;95%confidence interval[CI]50.2%–63.3%)received *** patients that received TXA,a higher proportion of patients presented with shock index>1(70.68%vs.57.43%)and higher Injury Severity Score(ISS>25;49.62%vs.23.76%).Administration of TXA was not associated with mortality at hospital discharge(odds ratio[OR]0.86,95%CI 0.31–2.38).CONCLUSIONS:Among injured Irish patients presenting with hemorrhagic shock,TXA was administered to 56.8%of *** administered with TXA were on average more severely ***,a mortality benefit could not be demonstrated.

关键词： Tranexamic acid Shock Ireland Hemorrhage

Quantitative Variation in Water-Use efficiency across Water Regimes and Its Relationship with Circadian, Vegetative, Reproductive, and Leaf Gas-exchange Traits

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Molecular Plant 2012年第3期5卷 653-668页

作者： Christine e. edwards brent e. ewers C. Robertson McClung Ping Lou Cynthia Weinig Department of Botany University of Wyoming Laramie WY 82071 USA Present address： USACe eRDC Environmental Laboratory 3909 Halls Ferry Road Vicksburg MS 39180 USA Program in ecology University of Wyoming Laramie WY 82071 USA Department of Biological Sciences Dartmouth College Hanover NH 03755 USA

Drought limits light harvesting, resulting in lower plant growth and reproduction. One trait important for plant drought response is water-use efficiency （WUe）. We investigated （1） how the joint genetic architecture of WUe, reproductive characters, and vegetative traits changed across drought and well-watered conditions, （2） whether traits with distinct developmental bases （e.g. leaf gas exchange versus reproduction） differed in the environmental sensitivity of their genetic architecture, and （3） whether quantitative variation in circadian period was related to drought response in Brassica rapa. Overall, WUe increased in drought, primarily because stomatal conductance, and thus water loss, declined more than carbon fixation. Genotypes with the highest WUe in drought expressed the lowest WUe in well-watered conditions, and had the largest vegetative and floral organs in both treatments. Thus, large changes in WUe enabled some genotypes to approach vegetative and reproductive trait optima across environments. The genetic architecture differed for gas-exchange and vegetative traits across drought and well-watered conditions, but not for floral traits. Correlations between circadian and leaf gas-exchange traits were significant but did not vary across treatments, indicating that circadian period affects physiological function regardless of water availability. These results suggest that WUe is important for drought tolerance in Brassica rapa and that artificial selection for increased WUe in drought will not result in maladaptive expression of other traits that are correlated with WUe.

关键词： Brassica rapa drought ecophysiology floral traits G matrix leaf gas-exchange traits water-use efficiency vegetative traits

Numerical modelling of flow and transport in rough fractures

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Journal of Rock Mechanics and Geotechnical engineering 2014年第6期6卷 535-545页

作者： Scott Briggs Bryan W.Karney brent e.Sleep University of Toronto Toronto M5S 1A4 Canada

Simulation of flow and transport through rough walled rock fractures is investigated using the latticeBoltzmann method （LBM） and random walk （RW）, respectively. The numerical implementation isdeveloped and validated on general purpose graphic processing units （GPGPUs）. Both the LBM and RWmethod are well suited to parallel implementation on GPGPUs because they require only next-neighbourcommunication and thus can reduce expenses. The LBM model is an order of magnitude faster onGPGPUs than published results for LBM simulations run on modern CPUs. The fluid model is verified forparallel plate flow, backward facing step and single fracture flow; and the RWmodel is verified for pointsourcediffusion, Taylor-Aris dispersion and breakthrough behaviour in a single fracture. Both algorithmsplace limitations on the discrete displacement of fluid or particle transport per time step to minimise thenumerical error that must be considered during implementation. 2014 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting byelsevier B.V. All rights reserved.

关键词： Hydrogeology Fracture flow Solute transport Computational fluid dynamics Lattice Boltzmann method(LBM) Random walk(RW)

Assessing ventilation control strategies in underground parking garages

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Building Simulation 2021年第3期14卷 701-720页

作者： Afshin Faramarzi Jongki Lee brent Stephens Mohammad Heidarinejad Department of Civil Architecturaland Environmental EngineeringIllinois Institute of TechnologyChicagoILUSA

enclosed parking garages require mechanical ventilation fans to dilute concentrations of pollutants emitted from vehicles,which contributes to energy use and peak electricity *** study develops and applies a simulation framework combining multi-zone airflow and contaminant transport modeling,fan affinity laws,and realistic assumptions for vehicle traffic patterns and carbon monoxide(CO)emissions to improve our ability to predict the impacts of various ventilation control strategies on indoor air quality and fan energy use in parking *** simulation approach is validated using measured data from a parking garage case study and then applied to investigate fan energy use,peak power demand,and resulting CO concentrations for four different ventilation control strategies in a model underground parking garage under a variety of assumptions for model *** four ventilation control strategies evaluated include one simplistic schedule(i.e.,Always-On)and three demand-based strategies in which fan speed is a function of CO concentrations in the spaces,including Linear-Demand Control Ventilation(DCV),Standardized Variable Flow(SVF),and a simple On-Off *** estimated annual average fan energy consumption was consistently lowest with the Linear-DCV strategy,resulting in average(±standard deviation)energy savings across all modeled scenarios of 84.3%±0.4%,72.8%±3.6%,and 97.9%±0.1%compared to SVF,On-Off,and Always-On strategies,*** utility of the framework described herein is that it can be used to model energy and indoor air quality impacts of other parking garage configurations and control scenarios.

关键词： carbon monoxide demand control ventilation energy efficiency indoor air quality underground parking garage

On-chip frequency combs and telecommunications signal processing meet quantum optics

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Frontiers of Optoelectronics 2018年第2期11卷 134-147页

作者： Christian ReIMeR Yanbing ZHANG Piotr ROZTOCKI Stefania SCIARA Luis Romero CORTeS Mehedi ISLAM Bennet FISCHeR Benjamin WeTZeL Alfonso Carmelo CINO Sai Tak CHU brent little David MOSS Lucia CASPANI Jose AZANA Michael KUeS Roberto MORANDOTTI Institut National de la Recherche Scientifique - Centre energie Matrriaux et Telecommunications (INRS-EMT) 1650 Boulevard Lionel-Boulet Varennes Qurbec J3X 1S2 Canada Department of energy Information Engineering and Mathematical Models University of Palermo Palermo Italy Department of Physics & Astronomy University of Sussex Falmer Brighton BN1 9QH UK Department of Physics and Material Science City University of Hong Kong Tat Chee Avenue Hong Kong China State Key Laboratory of Transient Optics and Photonics Xi'an Institute of Optics and Precision Mechanics Chinese Academy of Sciences Xi'an 710119 China Centre for Micro Photonics Swinburne University of Technology Hawthorn Victoria 3122 Australia Institute of Photonics Department of Physics University of Strathclyde Glasgow G1 1RD UK School of engineering University of Glasgow Rankine Building Oakfield Avenue Glasgow G 12 8LT UK Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of China Chengdu 610054 China National Research University of Information Technologies Mechanics and Optics St Petersburg 197101 Russia

entangled optical quantum states are essential towards solving questions in fundamental physics and are at the heart of applications in quantum information science. For advancing the research and development of quantum technologies, practical access to the generation and manipulation of photon states carrying significant quantum resources is required. Recently, integrated photonics has become a leading platform for the compact and cost- efficient generation and processing of optical quantum states. Despite significant advances, most on-chip non- classical light sources are still limited to basic bi-photon systems formed by two-dimensional states （i.e., qubits）. An interesting approach beating large potential is the use of the time or frequency domain to enabled the scalable on- chip generation of complex states. In this manuscript, we review recent efforts in using on-chip optical frequency combs for quantum state generation and telecommunica- tions components for their coherent control. In particular, the generation of bi- and multi-photon entangled qubit states has been demonstrated, based on a discrete time domain approach. Moreover, the on-chip generation of high-dimensional entangled states （quDits） has recentlybeen realized, wherein the photons are created in a coherent superposition of multiple pure frequency modes. The time- and frequency-domain states formed with on-chip frequency comb sources were coherently manipulated via off-the-shelf telecommunications compo- nents. Our results suggest that microcavity-based entangled photon states and their coherent control using accessible telecommunication infrastructures can open up new venues for scalable quantum information science.

关键词： nonlinear optics quantum optics entangledphotons