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A review of multiple optical vortices generation: methods and applications

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Frontiers of Optoelectronics 2019年第1期12卷 52-68页

作者： Long ZHU Jian WANG Wuhan National Laboratory for Optoelectronics School of Optical and Electronic InformationHuazhong University of Science and TechnologyWuhan 430074China

Optical vortices carrying orbital angular momentum(OAM)have attracted increasing interest in recent years.Optical vortices have seen a variety of emerging applications in optical manipulation,optical trapping,optical tweezers,optical vortex knots,imaging,microscopy,sensing,metrology,quantum information processing,and optical communications.In various optical vortices enabled applications,the generation of multiple optical vortices is of great importance.In this review article,we focus on the methods of multiple optical vortices generation and its applications.We review the methods for generating multiple optical vortices in three cases,i.e.,1-to-N collinear OAM modes,1-to-N OAM mode array and N-to-N collinear OAM modes.Diverse applications of multiple OAM modes in optical communications and non-communication areas are presented.Future trends,perspectives and opportunities are also discussed.

关键词： optical communications optical vortices orbital angular momentum (OAM) mode-division multiplexing (MDM) mode multicasting

Creation of topological vortices using Pancharatnam-Berry phase liquid crystal holographic plates

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Chinese Physics B 2020年第4期29卷 89-93页

作者：郭旭岳钟进展李鹏魏冰妍刘圣赵建林 MOE Key Laboratory of Material Physics and Chemistry under Extraordinary Conditions and Shaanxi Key Laboratory of Optical Information TechnologySchool of Physical Science and TechnologyNorthwestern Polytechnical UniversityXi'an 710129China

Recently,physical fields with topological configurations are evoking increasing attention due to their fascinating structures both in fundamental researches and practical applications.Therein,topological light fields,because of their unique opportunity of combining experimental and analytical studies,are attracting more interest.Here,based on the Pancharatnam-Berry(PB)phase,we report the creation of Hopf linked and Trefoil knotted optical vortices by using phaseonly encoded liquid crystal(LC)holographic plates.Utilizing scanning measurement and the digital holographic interference method,we accurately locate the vortex singularities and map these topological nodal lines in three-dimensions.Compared with the common methods realized by the spatial light modulator(SLM),the phase-only LC plate is more efficient.Meanwhile,the smaller pixel size of the LC element reduces the imperfection induced by optical misalignment and pixellation.Moreover,we analyze the influence of the incident beam size on the topological configuration.

关键词： topological vortices Pancharatnam-Berry phase liquid crystal phase singularity hologram

Evolution of the ring-like vortices and spike structure in transitional boundary layers

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Science China(Physics,Mechanics & Astronomy) 2010年第3期53卷 514-520页

作者： OLIVEIRA Maria Department of Mathematics University of Texas at Arlington Arlington Texas 76010 USA

At the late stage of transitional boundary layers, the nonlinear evolution of the ring-like vortices and spike structures and their effects on the surrounding flow were studied by means of direct numerical simulation with high order accuracy. A spatial transition of the flat-plate boundary layers in the compressible flow was conducted. Detailed numerical results with high resolution clearly represented the typical vortex structures, such as ring-like vortices and so on, and induced ejection and sweep events. It was verified that the formation of spike structures in transitional boundary layers had close relationship with ring-like vortices. Especially, compared to the newly observed positive spike structure in the experiments, the same structure was found in the present numerical simulations, and the mechanism was also studied and analyzed.

关键词： boundary layer transition ring-like vortices spike structure direct numerical simulation

On Ginzburg-Landau vortices of Superconducting Thin Films

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Acta Mathematica Sinica,English Series 2006年第2期22卷 469-476页

作者： Shi Jin DING Qiang DU Department of Mathematics South China Normal University Department of Mathematics Penn State University

In this paper, we discuss the vortex structure of the superconducting thin films placed in a magnetic field. We show that the global minimizer of the functional modelling the superconducting thin films has a bounded number of vortices when the applied magnetic field hex 〈 Hc1 ＋ K log ｜ logε｜ where Hc1 is the lower critical field of the film obtained by Ding and Du in SIAM J. Math. Anal., 2002. The locations of the vortices are also given.

关键词： Superconducting thin films Global minimizer vortices Pinning mechanism

INTERACTION BETWEEN LONGITUDINAL vortices AND FLAT PLATE BOUNDARY LAYER

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Acta Mechanica Sinica 1991年第3期7卷 218-226页

作者：孙青马晖扬徐书轩 University of Science and Technology of China Hefei 230026China

The interaction between longitudinal vortices and flat plate boundary layer has been studied numerically for both laminar and turbulent flow situations.The vortices are assumed to be placed in an otherwise two-dimensional boundary layer flow.The flow is assumed to be incompressible and steady.Consid- ering the fact that the velocity,vorticity and temperature gradients in the transverse directions are much larger than the longitudinal(streamwise)gradients for these flows,the original Navier Stokes equations are parabolized in the streamwise direction.A simple model,based on Boussinesq hypothesis,is used for turbu- lent flow.The discretized equations are then solved step by step in the streamwise direction,using an iterative procedure at each station.Numerical solutions have been obtained for different parameters,such as the Reynolds number,the circulation and the initial position of the vortices.The computed flow patterns and the skin friction coefficient and Stanton number are found to be qualitatively consistent with available experimental results.It is shown that the interaction between the vortices and the boundary layer may severely disturb the boundary layer flow field and thus considerably increase the local skin friction and heat transfer rate on surface of an aircraft.

关键词： vortices boundary layers

The 3D solitons and vortices in 3D discrete monatomic lattices with cubic and quartic nonlinearity

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Chinese Physics B 2006年第2期15卷 253-265页

作者：徐权田强 Scientific and Technological Office Daqing Normal University Daqing 163712 China Department of Physics Beijing Normal University Beijing 100875 China

By virtue of the method of multiple-scale and the quasi-discreteness approach, we have discussed the nonlinear vibration equation of a 3D discrete monatomic lattice with its nearest-neighbours interaction. The 3D simple cubic lattices have the same localized modes as a 1D discrete monatomic chain with cubic and quartic nonlinearity. The nonlinear vibration in the 3D simple cubic lattice has 3D distorted solitons and 3D envelop solitons in the direction of kx = ky = kz = k and k = ±π/6α0 in the Brillouin zone, as well as has 3D vortices in the direction of kx = ky = kz = k and k = ±π/α0 in the Brillouin zone.

关键词： 3D simple cubic lattice Brillouin zone envelop soliton distorted soliton vortices

Carrier Envelope Phase Description for an Isolated Attosecond Pulse by Momentum vortices

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Chinese Physics Letters 2019年第6期36卷 24-28页

作者：李猛张贵忠丁欣姚键铨 College of Precision Instrument and Optoelectronics Engineering Tianjin University Civil Aviation Meteorological Institute Key Laboratory of Operation Programming & Safety Technology of Air Traffic Management Civil Aviation University of China

As a crucial parameter for a few-cycle laser pulse, the carrier envelope phase(CEP) substantially determines the laser waveform. We propose a method to directly describe the CEP of an isolated attosecond pulse(IAP) by the vortex-shaped momentum pattern, which is generated from the tunneling ionization of a hydrogen atom by a pair of time-delayed, oppositely and circularly polarized IAP-IR pulses. Superior to the angular streaking method that characterizes the CEP in terms of only one streak, our method describes the CEP of an IAP by the features of multiple streaks in the vortex pattern. The proposed method may open the possibility of capturing sub-cycle extreme ultraviolet dynamics.

关键词： Isolated Attosecond Pulse Momentum vortices carrier envelope phase(CEP)

Attosecond twisted beams from high-order harmonicgeneration driven by optical vortices

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High Power Laser Science and Engineering 2017年第1期5卷 12-19页

作者： Carlos Hernandez-Garcia Laura Rego Julio San Roman Antonio Picon Luis Plaja Grupo de Investigacion en Aplicaciones del Laser y Fotonica Departamento de Fisica AplicadaUniversity of SalamancaE-37008SalamancaSpain Argonne National Laboratory Argonne1L 60439USA

Optical vortices are structures of the electromagnetic field with a spiral phase ramp about a point-phase singularity,carrying orbital angular momentum(OAM). Recently, OAM has been imprinted to short-wavelength radiation through high-order harmonic generation(HHG), leading to the emission of attosecond twisted beams in the extreme-ultraviolet(XUV) regime. We explore the details of the mapping of the driving vortex to its harmonic spectrum. In particular, we show that the geometry of the harmonic vortices is convoluted, arising from the superposition of the contribution from the short and long quantum paths responsible of HHG. Finally, we show how to take advantage of transverse phase-matching to select twisted attosecond beams with different spatiotemporal properties.

关键词： attosecond science extreme-ultraviolet vortices high harmonic generation orbital angular momentum twisted beams vortexbeams

A Numerical Prediction of Tip vortices from Tandem Propellers in the Counter-Rotating Type Tidal Stream Power Unit

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Journal of Power and Energy Engineering 2017年第12期5卷 66-74页

作者： Hoyun Jung Toshiaki Kanemoto Pin Liu Institute of Ocean Energy Saga University Saga Japan

Ocean energy has a potential of providing a large amount of renewable energy around the world. One of the forms of ocean energy, tidal stream power is widely recognized as the continuous, predictable and eco-friendly ocean energy source. Unique tandem propellers that can counter-rotate have been designed to generate electric power effectively from a tidal stream. This type of power unit has several advantages compare to the conventional unit with a single propeller. At the design of the tidal stream power unit, it is important to investigate the structure of the tip vortex tubes shedding to predict the load of the propeller. In this research, we investigated the tip vortex shedding using the CFD method for the conventional single propeller and counter-rotating type tandem propellers and estimated the performance efficiency using RANS (Reynolds Averaged Navier-Stokes) model and we confirmed the limitation of RANS model on the calculation of the tip vortex stretching.

关键词： Tidal Stream Power Unit Counter-Rotation CFD (Computational Fluid Dynamics) Tip vortices MRF (Multiple Reference Frame) Tandem Propellers