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Full-vectorial finite-difference beam propagation method based on the modified alternating direction implicit method 被引量:1
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作者 肖金标 孙小菡 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第8期1824-1830,共7页
A modified alternating direction implicit algorithm is proposed to solve the full-vectorial finite-difference beam propagation method formulation based on H fields. The cross-coupling terms are neglected in the first ... A modified alternating direction implicit algorithm is proposed to solve the full-vectorial finite-difference beam propagation method formulation based on H fields. The cross-coupling terms are neglected in the first sub-step, but evaluated and doubly used in the second sub-step. The order of two sub-steps is reversed for each transverse magnetic field component so that the cross-coupling terms are always expressed in implicit form, thus the calculation is very efficient and stable. Moreover, an improved six-point finite-difference scheme with high accuracy independent of specific structures of waveguide is also constructed to approximate the cross-coupling terms along the transverse directions. The imaginary-distance procedure is used to assess the validity and utility of the present method. The field patterns and the normalized propagation constants of the fundamental mode for a buried rectangular waveguide and a rib waveguide are presented. Solutions are in excellent agreement with the benchmark results from the modal transverse resonance method. 展开更多
关键词 beam propagation method alternating direction implicit algorithm finite difference optical waveguides integrated optics
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Wavelet Beam Propagation Method for Study the Integrated Optical Waveguide
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作者 LI Zhengbin, FU Jumei ,FEN Engxin (Electromagn. and Commun. Lab.,Xi’an Jiaotong University, Xi’an,710049,CHN) 《Semiconductor Photonics and Technology》 CAS 1999年第1期1-8,共8页
A new numerical technique based on the wavelet derivative operator is presented as an alternative to BPM to study the integrated optical waveguide. The wavelet derivative operator is used instead of FFT/IFFT or finite... A new numerical technique based on the wavelet derivative operator is presented as an alternative to BPM to study the integrated optical waveguide. The wavelet derivative operator is used instead of FFT/IFFT or finite difference to calculate the derivatives of the transverse variable in the Helmholtz equation. Results of numerically simulating the injected field at z =0 are exhibited with Gaussian distribution in transverse direction propagating through the two dimensional waveguides (with linear and/or nonlinear refractive index) , which are similar to those in the related publications. Consequently it is efficient and needs not absorbing boundary by introducing the interpolation operator during calculating the wavelet derivative operator. The iterative process needs fewer steps to be stable. Also, when the light wave meets the changes of mediums, the wavelet derivative operator has the adaptive property to adjust those changes at the boundaries. 展开更多
关键词 beam propagation Method Waveguide Wavelet Derivative Operator Sobolev Space Soliton(s)
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Generalization and propagation of spiraling Bessel beams with a helical axicon 被引量:2
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作者 Sun Qiong-Ge Zhou Ke-Ya +2 位作者 Fang Guang-Yu Liu Zheng-Jun Liu Shu-Tian 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第1期234-243,共10页
A generalized type of spiral Bessel beam has been demonstrated by using a spatially displaced helical axicon (HA). The topological charge of the spiraling Bessel beams is determined by the order of the input Laguerr... A generalized type of spiral Bessel beam has been demonstrated by using a spatially displaced helical axicon (HA). The topological charge of the spiraling Bessel beams is determined by the order of the input Laguerre Gaussian (LG) beam and the topological charge of the HA. The obtained spiraling Bessel beams have an LG type of modulation along their propagation direction and exhibit annihilation-reconstruction properties. Theoretical analysis is presented, including that of the stability, propagation distance, topological charge, and spiraling dynamic characteristics. The mathematical and numerical results show that the propagation distance and helical revolution of the spiraling Bessel beams can be controlled through choosing appropriate radius of the HA. 展开更多
关键词 Bessel beam helical axicon beam propagation spiral beam
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Three-dimensional beam propagation method based on the variable transformed Galerkin's method 被引量:3
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作者 XIAOJinbiao SUNXiaohan ZHANGMingde 《Science in China(Series F)》 2004年第1期34-43,共10页
A novel three-dimensional beam propagation method (BPM) based on the variable transformed Galerkin's method is introduced for simulating optical field propagation in three-dimensional dielectric structures. The in... A novel three-dimensional beam propagation method (BPM) based on the variable transformed Galerkin's method is introduced for simulating optical field propagation in three-dimensional dielectric structures. The infinite Cartesian x-y plane is mapped into a unit square by a tangent-type function transformation. Consequently, the infinite region problem is converted into the finite region problem. Thus, the boundary truncation is eliminated and the calculation accuracy is promoted. The three-dimensional BPM basic equation is reduced to a set of first-order ordinary differential equations through sinusoidal basis function, which fits arbitrary cladding optical waveguide, then direct solution of the resulting equations by means of the Runge-Kutta method. In addition, the calculation is efficient due to the small matrix derived from the present technique. Both z-invariant and z-variant examples are considered to test both the accuracy and utility of this approach. 展开更多
关键词 three-dimensional beam propagation method variable transformed Galerkin's method optical field propagation three-dimensional dielectric structures.
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Propagation properties of off-axis Hermite-cosh-Gaussian beam combinations through a first-order optical system
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作者 唐前进 陈大明 +1 位作者 于永爱 胡企铨 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第11期2609-2617,共9页
Based on the Collins integral formula, the analytic expressions of propagation of the coherent and the incoherent off-axis Hermite-cosh-Gaussian (HChG) beam combinations with rectangular symmetry passing through a p... Based on the Collins integral formula, the analytic expressions of propagation of the coherent and the incoherent off-axis Hermite-cosh-Gaussian (HChG) beam combinations with rectangular symmetry passing through a paraxial first-order optical system are derived, and corresponding numerical examples are given and analysed. The resulting beam quality is discussed in terms of power in the bucket (PIB). The study suggests that the resulting beam cannot keep the initial intensity shape during the propagation and the beam quality for coherent mode is not always better than that for incoherent mode. Reviewing the numerical simulations of Gaussian, Hermite-Gaussian (HG) and cosh- Gaussian (ChG) beam combinations indicates that the Hermite polynomial exerts a chief influence on the irradiance profile of composite beam and far field power concentration. 展开更多
关键词 laser technology beam propagation beam combination HChG
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An improved three-dimensional full-vectorial finite-difference imaginary-distance beam propagation method
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作者 XIAO Jinbiao LIU Xu CAI Chun FAN Hehong SUN Xiaohan 《Science in China(Series F)》 2006年第4期516-532,共17页
A modified alternating direction implicit approach is proposed to discretize the three-dimensional full-vectorial beam propagation method (3D-FV-BPM) formulation along the longitudinal direction. The cross-coupling ... A modified alternating direction implicit approach is proposed to discretize the three-dimensional full-vectorial beam propagation method (3D-FV-BPM) formulation along the longitudinal direction. The cross-coupling terms (CCTs) are neglected at the first substep, and then double used at the second substep. The order of two substeps is reversed for each transverse electric field component so that the CCTs are always expressed in an implicit form, thus the calculation is efficient and stable. Based on the multinomial interpolation, a universal finite difference scheme with a high accuracy is developed to approximate the 3D-FV-BPM formulation along the transverse directions, in which the discontinuities of the normal components of the electric field across the abrupt dielectric interfaces are taken into account and can be applied to both uniform and non-uniform grids. The corresponding imaginary-distance procedure is first applied to a buried rectangular and a GaAs-based deeply-etched rib waveguide. The field patterns and the normalized propagation constants of the fundamental and the first order modes are presented and the hybrid nature of the full-vectorial guided-modes is demonstrated, which shows the validity and utility of the present approach. Then the modal characteristics of the deeply- and shallow-etched rib waveguides based on the InGaAsp/InGaAsP strained multiple quantum wells in InP substrate are investigated in detail. The results are necessary for modeling and the design of the planar lightwave circuits or photonic integrated circuits based on these waveguides. 展开更多
关键词 optical waveguides full-vectorial guided-modes beam propagation method finite difference photonic integrated circuits.
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A Construction of Beam Propagation Methods for Optical Waveguides
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作者 Xavier Antoine Pierre Dreyfuss Karim Ramdani 《Communications in Computational Physics》 SCIE 2009年第8期565-576,共12页
This paper presents a systematic method to derive Beam Propagation Models for optical waveguides.The technique is based on the use of the symbolic calculus rules for pseudodifferential operators.The cases of straight ... This paper presents a systematic method to derive Beam Propagation Models for optical waveguides.The technique is based on the use of the symbolic calculus rules for pseudodifferential operators.The cases of straight and bent optical waveguides are successively considered. 展开更多
关键词 Bent waveguides beam propagation Method OPTICS
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Modified Wide-angle Beam Propagation Method Using Douglas Operators
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作者 JU Zhenle,FU Junmei,FENG Enxin (Lab. of Microwave Eng. and Opt. Commun.Tech.,Xi’an Jiaotong University,Xi’an 710049,CHN) 《Semiconductor Photonics and Technology》 CAS 1997年第4期269-273,共5页
A modified wide-angle beam propagation based on the Douglas operators is presented.The truncation error in the modified wide-angle beam propagation is reduced to o (Δ x ) 4 in the transverse direction nearly wi... A modified wide-angle beam propagation based on the Douglas operators is presented.The truncation error in the modified wide-angle beam propagation is reduced to o (Δ x ) 4 in the transverse direction nearly without any increase of the computation time,whereas the error in the ordinary wide-angle beam propagation method is typically o (Δ x ) 2.With trivial programming changes,the accuracy is higher,especially in wide-angle propagation. 展开更多
关键词 Douglas Operators Guidewave Photonic Devices Modified Wide beam propagation Method
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Gaussian Beam Propagation in a Kerr Type Metamaterial Medium Using ABCD Matrix Method
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作者 A.Keshavarz M.Naseri 《Communications in Theoretical Physics》 SCIE CAS CSCD 2016年第8期231-236,共6页
In this paper, a split step ABCD matrix method is suggested to investigate Gaussian beam propagation in a Kerr type metamaterial medium. This method is based on dividing the medium interval into subsequent steps.Meanw... In this paper, a split step ABCD matrix method is suggested to investigate Gaussian beam propagation in a Kerr type metamaterial medium. This method is based on dividing the medium interval into subsequent steps.Meanwhile, Gaussian beam profile in every step is obtained by finding the ABCD matrix of that particular step, and is used to find the ABCD matrix of the next step. Results of the suggested matrix method have been compared with the results of numerical split-step Fourier method for a Kerr medium, which indicates a good agreement. Then, we use the ABCD matrix to investigate Gaussian beams propagation in a Kerr type metamaterial, which is also in agreement with pervious results by other methods. 展开更多
关键词 ABCD matrix method Kerr type metamaterials paraxial beam beam propagation
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Propagation of Partially Coherent Elegant Hermite-Cosh-Gaussian Beam in Non-Kolmogorov Turbulence
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作者 张文赋 连洁 +5 位作者 王英顺 胡雪元 孙兆宗 赵明琳 王莹 李蒙蒙 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第6期69-72,共4页
Based on the extended Huygens-Fresnel integral, analytical propagation expressions for the rms beam width and angular of partially coherent elegant Hermite cosh Caussian beam (EHChCB) in non-Kolmogorov turbulence ar... Based on the extended Huygens-Fresnel integral, analytical propagation expressions for the rms beam width and angular of partially coherent elegant Hermite cosh Caussian beam (EHChCB) in non-Kolmogorov turbulence are derived. The effects of exponent value, inner and outer scales of non-Kolmogorov turbulence on partially coherent EFIChGB are investigated quantitatively. 展开更多
关键词 Figure propagation of Partially Coherent Elegant Hermite-Cosh-Gaussian beam in Non-Kolmogorov Turbulence
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Transversal reverse transformation of anomalous hollow beams in strongly isotropic nonlocal media 被引量:1
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作者 戴志平 杨振军 +2 位作者 张书敏 庞兆广 游开明 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第7期452-458,共7页
Based on the nonlocal nonlinear Schr6dinger equation, the propagation properties of anomalous hollow beams in strongly isotropic nonlocal media are investigated. The analytical expressions of the beam propagation, the... Based on the nonlocal nonlinear Schr6dinger equation, the propagation properties of anomalous hollow beams in strongly isotropic nonlocal media are investigated. The analytical expressions of the beam propagation, the on-axis intensity and the beam width are obt.ained. The results show that the evolution of the beam is periodical and the input power is the most important parameter. The input power determines the variation of the period. Furthermore, it is found that there exists a critical input power in the x direction and in the y direction separately when the initial beam widths in the two transversal directions are unequal. The beam width remains invariant in the corresponding transversal direction when the input power equals the critical power in one of the transversal directions. Selecting a properinput power, the beam can be broadened or compressed in the two transversal directions at the same time, In particular, the beam can be broadened (compressed) in one transversal direction, whereas in the other transversal direction, it is compressed (broadened), i.e., the transversal reverse transformation. 展开更多
关键词 spatial nonlocality beam propagation transversal reverse transformation
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Analytical structure of Hermite Gaussian beam in far field
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作者 周国泉 陈亮 储修祥 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第9期2709-2715,共7页
Based on the vectorial structure of electromagnetic beam and the method of stationary phase, the analytical structure of Hermite Gaussian beam in far field is presented. The structural energy flux distributions are al... Based on the vectorial structure of electromagnetic beam and the method of stationary phase, the analytical structure of Hermite Gaussian beam in far field is presented. The structural energy flux distributions are also investigated in the far field. The structural pictures of some Hermite Gaussian beams are depicted in the far field. As the structure of Hermite Gaussian beam is dominated by the transverse mode numbers and the initial transverse Gaussian half width, it is more complex than that of Gaussian beam. The ratios of the structural energy fluxes to the whole energy flux are independent of the transverse mode numbers and the initial transverse Gaussian half width. The present research reveals the internal vectorial structure of Hermite Gaussian beam from other viewpoint. 展开更多
关键词 Hermite Gaussian beam vectorial structure method of stationary phase beam propagation
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M2-factor of high-power laser beams through a multi-apertured ABCD optical system
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作者 Xiangmei Zeng Meizhi Zhang +2 位作者 Dongmei Cao Dingyu Sun Hua Zhou 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第6期191-196,共6页
Based on the generalized truncated second-order moments,an approximate analytical formula of the beam propagation factor M^2 of high-power laser beams passing through the optical system with multiple hard-edged apertu... Based on the generalized truncated second-order moments,an approximate analytical formula of the beam propagation factor M^2 of high-power laser beams passing through the optical system with multiple hard-edged apertures is deduced.Numerical examples of the beams passing through an aperture-spatial filter are enclosed,and the influences of amplitude modulations(AMs)and phase fluctuations(PFs)on the beam propagation quality of high-power laser beams passing through the multi-apertured ABCD optical system are considered and discussed.It is shown that PFs are able to degrade the beam propagation quality of laser beams more than AMs when the high-power laser beams passing through the aperture-spatial filter,furthermore,one or two aperture-lens optical systems configured appropriate aperture parameters are both able to upgrade the beam propagation quality of high-power laser beams.The M2 factor of Gaussian beam passing through the multi-aperture optical system is a special case in this paper. 展开更多
关键词 amplitude modulations(AMs) phase fluctuations(PFs) multiple hard-edged aperture beam propagation factor
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M^2 factor of four-petal Gaussian beam
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作者 周国泉 樊艳 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第10期3708-3712,共5页
Based on the second-order moments, this paper derives an analytical expression of the M^2 factor of four-petal Gaussian beam. The results show that the M^2 factor is only determined by the beam order n. The correspond... Based on the second-order moments, this paper derives an analytical expression of the M^2 factor of four-petal Gaussian beam. The results show that the M^2 factor is only determined by the beam order n. The corresponding numerical calculations are also given. As the beam order increases, the augment of M^2 factor is disciplinary. As the expression of M^2 factor is expressed in series form and becomes more complicated, a new concise formula of M^2 factor is also presented by using curve fitting of numerical calculations. When 3 ≤ n ≤ 200, the maximum error rate of fitting formula will not exceed 2.6% and the average error rate is 0.28%. This research is helpful to the applications of four-petal Gaussian beam. 展开更多
关键词 beam propagation four-petal Gaussian beam second-order moment
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Hollow Gaussian beams in strongly nonlocal nonlinear media
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作者 杨振军 陆大全 +2 位作者 胡巍 郑一周 高星辉 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第12期310-317,共8页
The propagation of hollow Gaussian beams in strongly nonlocal nonlinear media is studied in detail. Two analytical expressions are derived. For hollow Gaussian beams, the intensity distribution always evolves periodic... The propagation of hollow Gaussian beams in strongly nonlocal nonlinear media is studied in detail. Two analytical expressions are derived. For hollow Gaussian beams, the intensity distribution always evolves periodically. However the second-order moment beam width can keep invariant during propagation if the input power is equal to the critical power. The interaction of two hollow Gaussian beams and the vortical hollow Gaussian beams are also discussed. The vortical hollow Gaussian beams with an appropriate topological charge can keep their shapes invariant during propagation. 展开更多
关键词 strong nonlocality hollow Gaussian beam beam propagation
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Method for extracting angle-domain common image gathers in Kirchhoff beam migration 被引量:1
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作者 ZHANG Zhihou YAO Yu +2 位作者 SUN Hui YANG Junjie LI Meng 《Global Geology》 2020年第3期149-154,共6页
Kirchhoff beam migration is a simplified Gaussian beam migration,which omits the dynamic information and can calculate multi-arrival traveltime,so it is a high-precision and fast seismic imaging method.In the imaging ... Kirchhoff beam migration is a simplified Gaussian beam migration,which omits the dynamic information and can calculate multi-arrival traveltime,so it is a high-precision and fast seismic imaging method.In the imaging process,extracting common image gathers can be used for velocity analysis,improving the accuracy of modeling and imaging quality.Compared with the conventional common image gathers extracting methods,the angle-domain common image gathers extracting method can avoid the artifacts caused by multi-arrival seismic waves.The authors present a new method of extracting common image gathers in angle-domain from Kirchhoff beam migration and verify the method by numerical calculations. 展开更多
关键词 Kirchhoff beam migration angle-domain common image gathers beam propagator travel time calculation
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Artificial boundary conditions for Euler–Bernoulli beam equation 被引量:1
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作者 Shao-Qiang Tang Eduard G.Karpov 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2014年第5期687-692,共6页
In a semi-discretized Euler-Bernoulli beam equa- tion, the non-nearest neighboring interaction and large span of temporal scales for wave propagations pose challenges to the effectiveness and stability for artificial ... In a semi-discretized Euler-Bernoulli beam equa- tion, the non-nearest neighboring interaction and large span of temporal scales for wave propagations pose challenges to the effectiveness and stability for artificial boundary treat- ments. With the discrete equation regarded as an atomic lattice with a three-atom potential, two accurate artificial boundary conditions are first derived here. Reflection co- efficient and numerical tests illustrate the capability of the proposed methods. In particular, the time history treatment gives an exact boundary condition, yet with sensitivity to nu- merical implementations. The ALEX (almost EXact) bound- ary condition is numerically more effective. 展开更多
关键词 Euler-Bernoulli beam. Artificial boundary con- dition - Wave propagation
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High-Power Ridge-Waveguide Tapered Diode Lasers at 980nm
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作者 李璟 马骁宇 刘媛媛 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第5期645-650,共6页
High-power ridge-waveguide tapered InGaAs-AlGaAs lasers emitting at 980nm were fabricated. Lasers with a total length L = 1850μm and different lengths of the ridge waveguide Lrw were processed to study the influence ... High-power ridge-waveguide tapered InGaAs-AlGaAs lasers emitting at 980nm were fabricated. Lasers with a total length L = 1850μm and different lengths of the ridge waveguide Lrw were processed to study the influence of the straight section on the spatial mode filtering. When Lrw is 450μm, the devices have the optimized maxi- mum output power and beam quality,and the output power P is 4. 28W. The beam propagation ratio M2 is 3. 79 at 1W. 展开更多
关键词 tapered ridge-waveguide 980nm beam propagation factor
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Semi-vectorial analysis of a compact wavelength demultiplexer based on the tapered multimode interference coupler 被引量:1
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作者 肖金标 刘旭 +1 位作者 蔡纯 孙小菡 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第7期2015-2022,共8页
Based on a parabolically tapered multimode interference (MMI) coupler with a deep-etched SiO2/SiON rib waveguide, a compact wavelength demultiplexer operating at 1.30 and 1.55 μm wavelengths is proposed and analyse... Based on a parabolically tapered multimode interference (MMI) coupler with a deep-etched SiO2/SiON rib waveguide, a compact wavelength demultiplexer operating at 1.30 and 1.55 μm wavelengths is proposed and analysed by using three-dimensional semi-vectorial finite-difference beam propagation method (3D-SV-FD-BPM). The results show that a MMI section of 330.0 μm in length, which is only 76% length of a straight MMI coupler, is achieved with the contrasts of 42.3 and 39.2dB in quasi-TE mode, and 38.4 and 37.8dB in quasi-TM mode at wavelengths 1.30 and 1.55μm, respectively, and the insertion losses below 0.2dB at both wavelengths and in both polarization states, The alternating direction implicit algorithm with the Crank-Nicholson scheme is applied to the discretization of the 3D-SV-FD-BPM formulation along the longitudinal direction. Moreover, a modified FD scheme is constructed to approximate the resulting equations along the transverse directions, in which the discontinuities of the derivatives of magnetic field components Hy and Hx along the vertical and horizontal interfaces, respectively, are involved. 展开更多
关键词 wavelength demultiplexer multimode interference beam propagation method photonic integrated circuits
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Theoretical investigation of band-gap and mode characteristics of anti-resonance guiding photonic crystal fibres 被引量:1
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作者 苑金辉 桑新柱 +5 位作者 余重秀 忻向军 张锦龙 周桂耀 李曙光 侯蓝田 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第2期302-310,共9页
With the full-vector plane-wave method (FVPWM) and the full-vector beam propagation method (FVBPM), the dependences of the band-gap and mode characteristics on material index and cladding structure parameter in an... With the full-vector plane-wave method (FVPWM) and the full-vector beam propagation method (FVBPM), the dependences of the band-gap and mode characteristics on material index and cladding structure parameter in anti- resonance guiding photonic crystal fibres (ARGPCFs) are sufficiently analysed. An ARGPCF operating in the near- infrared wavelength is shown. The influences of the high index cylinders, glass interstitial apexes and silica structure on the characteristics of band-gaps and modes are deeply investigated. The equivalent planar waveguide theory is used for analysing such an ARGPCF filled by the isotropic materials, and the resonance and the anti-resonance characteristics r:~n h~ w~|] r^r~dlrtpd 展开更多
关键词 anti-resonance guiding photonic crystal fibres full-vector plane-wave method full-vector beam propagation method band-gap and mode characteristics
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