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light propagation characteristics through the annular coupled-cavity waveguides based on the two-dimensional square-lattice photonic crystal

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Optoelectronics Letters 2011年第2期7卷 129-132页

作者：冯帅李予喜敖玲任承 School of Science Minzu University of China School of Optoelectronic Information Science and Technology Yantai University

The light propagation characteristics through the annular coupled-resonator cavity waveguides are systematically analyzed by the finite-difference time-domain (FDTD) method. It is found that this kind of waveguide has more minbands owing to the increasing of the cavity’s size, compared with the traditional line-typed coupled-resonator waveguide. The group velocity of light propagation can be reduced for a further degree when the adjacent annular cavities are interlaced in the perpendicular direction, and a group velocity about 0.00067c (c is the light speed in vacuum) can be obtained.

关键词： Finite difference time domain method light propagation light velocity Photonic crystals Resonators Waveguides

As_2S_8 planar waveguide:refractive index changes following an annealing and irradiation and annealing cycle,and light propagation features

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Journal of Semiconductors 2011年第11期32卷 18-23页

作者：邹林儿王国日沈云陈抱雪矶守 Department of Physics Nanchang University School of Optical-Electrical and Computer Engineering University of Shanghai for Science and Technology Department of Chemical Engineering Tokyo University of Agriculture and Technology

The refractive index ofas-evaporatedamorphous semiconductor As2S8 film upon an annealing and saturation irradiation and annealing cycle is reversible. Upon successive treatment with annealing and non-saturation irradiation and further annealing, the refractive index of the as-evaporated amorphous semiconductor As2S8 film reaches a maximum value and then its reversibility occurs upon annealing. The annealing of the amorphous semiconductor AS2S8 films results in the stabilization of the structure through changes of the S-S bonds in the nearest environment, accompanied by a decrease of film thickness. The As2S8 planar waveguide after annealing （130 ℃） and saturation irradiation and annealing （130 ℃） shows a good propagation characteristic with ca, 0.27 dB/cm low propagation loss of the 632.8 nm guided mode.

关键词： amorphous semiconductor chalcogenide As2S8 waveguide refractive index light propagation

Parameterized Post-Post-Newtonian light propagation in the Field of One Spherically-Symmetric Body

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Communications in Theoretical Physics 2019年第12期71卷 1455-1460页

作者： Xiao-Yan Zhu Bo Yang Chun-Hua Jiang Wen-Bin Lin School of Mathematics and Physics University of South ChinaHengyang 421001China School of Physical Science and Technology Southwest Jiaotong UniversityChengdu 610031China

We derive a more generally parameterized post-post-Newtonian solution for the light propagation in the gravitational field of one spherically-symmetric *** on the solution for the light velocity,we give the formula of the light deflection when both the emitter and receiver are located in the regions far away from the body,which is the most important scenario in the real *** results can be applied to more metric theories of gravitation.

关键词： PPN spherically-symmetric metric light propagation light deflection

Extending the First—Order Post—Newtonian Scheme in Multiple Systems to the Second—Order Contributions to light propagation

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Chinese Physics Letters 2003年第2期20卷 195-198页

作者：须重明吴雪君 Departmentofphysics NanjingNormalUniversityNanjing210097

We extend the first-order post-Newtonian scheme in multiple systems presented by Damour-Soffel-Xu to the second-order contribution to light propagation without changing the virtue of the scheme on the linear partial differential equations of the potential and vector potential. The spatial components of the metric are extended to the second-order level both in a global coordinates (qij/c4) and a local coordinates (Qab/c4). The equations of qij (or Qab) are obtained from the field equations. The relationship between qij and Qab are also presented. In the special case of the solar system (isotropic condition is applied (qij = δijq)), we obtain the solution of q. Finally, a further extension of the second-order contributions in the parametrized post-Newtonian formalism is discussed.

关键词： light propagation

Voxel classification methodology for rapid Monte Carlo simulation of light propagation in complex media

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Chinese Optics Letters 2011年第4期9卷 75-78页

作者：任努努赵恒朱守平屈晓超刘宏亮胡振华梁继民田捷 Life Sciences Research Center School of Life Sciences and TechnologyXidian University Institute of Automation Chinese Academy of Science

Monte Carlo （MC） method is a statistical method for simulating photon propagation in media in the optical molecular imaging field. However, obtaining an accurate result using the method is quite time-consuming, especially because the boundary of the media is complex. A voxel classification method is proposed to reduce the computation cost. All the voxels generated by dividing the media are classified into three types （outside, boundary, and inside） according to the position of the voxel. The classified information is used to determine the relative position of the photon and the intersection between photon path and media boundary in the MC method. The influencing factors and effectiveness of the proposed method are analyzed and validated by simulation experiments.

关键词： Computer simulation light propagation Photons

propagation of light near the band edge in one-dimensional multilayers

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Chinese Physics B 2023年第4期32卷 370-373页

作者：唐洋范灵杰张彦彬李同宇沈唐尧石磊 State Key Laboratory of Surface Physics Key Laboratory of Micro-and Nano-Photonic Structures(Ministry of Education)and Department of PhysicsFudan UniversityShanghai 200433China

Optical systems offer rich modulation in light propagation, but sufficient quantitative descriptions lack when highly complex structures are considered since practical structures contain defects or imperfections. Here, we utilize a method combining a data-fitting method and a time-resolved system to describe light propagation near the band edges in onedimensional structures. Calculations after optimization of the method show little deviation to the measurements.

关键词： light propagation band edge light localization

Non-Paraxial propagation of Cylindrical Vector Vortex Beams in the Far-Field

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Chinese Physics Letters 2014年第7期31卷 85-89页

作者：郭利娜唐志列汪洁 School of Electronics and Information Guangdong Polytechnic Normal University Guangzhou 510665 School of Physics and Telecommunication Engineering Laboratory of Quantum Information Technology South China Normal University Guangzhou 510006

On the basis of the vectorial Rayleigh diffraction integral, the analytical expressions for the electric fields of cylindrical vector vortex beams （CVVBs） with an arbitrary polarization order in the far-field are derived, which helps us investigate the far-field properties of the CVVBs in the non-paraxial and paraxial regimes. Some detailed comparisons of the non-paraxial results with the paraxial results are made, which show that the polarization order and the ratio of beam waist width to wavelength play an important role in determining the non-paraxiality of CVVBs. In addition, the polarization order and the ratio of beam waist width to wavelength have a great impact on the diffraction effect and the divergent behavior of CVVBs in the far-field.

关键词： BEAM optics FRAUNHOFER region (Electromagnetism) light propagation OPTICAL polarization ELECTRIC fields RAYLEIGH scattering

Partially coherent vortex beams propagation in a turbulent atmosphere

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Chinese Optics Letters 2005年第10期3卷 559-561页

作者：张逸新汤敏霞陶纯堪 School of Science Southern Yangtze University Wuxi 214036 School of Electron-Optics Nanjing University of Science and Technology Nanjing 210014 Institute of Intelligence Southern Yangtze University Wuxi 214036

Based on the Rytov approximation and the cross-spectral density approximation for the mutual coherence function of the partially coherent field, the propagation properties of the partially coherent beams with optical vortices in turbulent atmosphere are discussed. The average intensity and the mutual coherence function of the partially coherent vortex beams propagation in weak turbulent atmosphere are obtained. It is shown that the vortex structure of the average cross-spectral density of partially coherent beams has the same helicoidally shape as that of the phase of the fully coherent Laguerre-Gauss beams in free space and the relative intensity of the beam is degraded by optical vortex.

关键词： Approximation theory Coherent light Density (optical) light propagation Turbulence Vortex flow

Definition and measurement of the beam propagation factor M^2 for chromatic laser beams

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Chinese Optics Letters 2006年第10期4卷 586-588页

作者：房滔叶訢牛金富徐剑秋 Shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesShanghai 201800

The concept of the beam propagation factor M^2 is extended for chromatic laser beams. The definition of the beam propagation factor can be generalized with the weighted effective wavelength. Using the new definition of factor M^2, the propagation of chromatic beams can be analyzed by the beam propagation factor M^2 as same as that of monochromatic beams. A simple method to measure the chromatic beam factor M^2 is demonstrated. The chromatic factor M^2 is found invariable while the laser beam propagates through the dispersion-free ABCD system.

关键词： Dispersion (waves) light propagation