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By using the methods of Hertz vector and angular spectrum transormation, the exact solution of non-paraxial elliptical Gaussion beam with general astigmatism based on Maxwell′s equations is obtained. We discussed its propagation characteristics. The results show that the orientation of the elliptical beam spot changes continuously as the beam propagates through isotropic media. Splitting or coupling of beam spots may occur for different initial spot size. This is very different from that of paraxial elliptical Gaussian beam. 相似文献
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This paper studies analytically and numerically the dynamics of two-dimensional elliptical Gaussian solitons in a "double-self-focusing" synthetic nonlocal media featuring elliptical and circular Gaussian response with different degrees of nonlocality.Based on the variational approach,it obtains the approximately analytical solution of such Gaussian elliptical solitons.It also computes the stability of the solitons by numerical simulations. 相似文献
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Far-field properties of non-paraxial elliptical Gaussian beams 总被引:2,自引:0,他引:2
By using the Rayleigh diffraction integral formula, a far-field asymptotic solution of the wave equation is found, which represents non-paraxial elliptical Gaussian beams. The basic properties of such beams are studied, and a comparison with the previous work is also made. 相似文献
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1.IntroductionLaserdiodehasbeenx`idelyusedinfibrc-opticcommunicat:onandopticaldisk$yctems.LaserbeamIsradiationangle(fullangu1aratha1f-maximumintensitypoint)ismeasuredbothparllelandPerpendiculartothcjunctionp1anclgenera1ly.o//=6,~1o",oJ-=2o"~5O':Inerasableopticaldisksystemsasmagneto-optica1disksystems,thelaserbcamiscollimatedandshapedtobecircularsymInetricbeaminordcrtoaquireahighintensityandhighqualityscanningbeamiPot,butitsoptica1systemiscomplicatedandeasyaddingassocialaberration.usingaellip… 相似文献
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对超短脉冲贝塞尔光束在近轴近似和非近轴情况下自由空间中的传输作了研究。结果表明,其空间波形在传输中保持贝塞尔形状不变,不受非近轴效应影响;然而当空间参数较大时,非近轴效应影响超短脉冲贝塞尔光束的时间波形。 相似文献
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Restoration of Decentered Gaussian Beam with the Combination of a Lens and a Gaussian Aperture 总被引:1,自引:0,他引:1
1 Introduction TheGaussianbeamisthefundamentalshapeofthelaserwithaspherical mirrorresonatorandwidelyusedtodescribeasinglemodelaser.Intheparaxialapproximation ,thedistributionofcomplexamplitudeofitremainsunchangedwhenitundergoestheFouriertransformorthe… 相似文献
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Propagation properties of partially coherent Hermiteben Gaussian beams through non-Kolmogorov turbulence 下载免费PDF全文
The propagation properties of partially coherent Hermite—Gaussian beams through non-Kolmogorov atmospheric turbulence are studied. The effects of non-Kolmogorov turbulence and beam nonparaxiality on the average intensity evolution and the beam-width spreading are stressed. It is found that the evolution of the average intensity distribution and the beam-width spreading depends on the generalized exponent factor, namely, on the non-Kolmogorov turbulence strength for the paraxial case. For the non-paraxial case the effect of the turbulence is negligible, while the beam-width spreading becomes very large. The analytical results are illustrated numerically and interpreted physically. 相似文献
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We construct wave packets concentrated near a single space-time trajectory of the semi-classical Hamiltonian for a Bloch electron
in a crystal lattice subject to slowly varying external electric and magnetic fields. The use of an analog of the Gaussian
beam Ansatz make it possible to construct packets for arbitrarily long finite times.
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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. 相似文献
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Scalar Approximation of Super-Gaussian Beams 总被引:1,自引:0,他引:1
CHEN Huilong CAO Qing FAN Dianyuan 《Chinese Journal of Lasers》1998,7(6):515-519
1IntroductionThemodesofacavitywithsuperGausianreflectivityareknownassuperGausianbeams,theydescribeawholefamilyoffielddistri... 相似文献
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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. 相似文献
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运用非傍轴光束传输的矢量矩理论,对非傍轴矢量高斯光束的传输特性进行了系统的研究.结果表明,基于二阶矩定义的横向光束宽度在光束传播过程中满足简单的双曲线变化规律,并且给出了光束传输因子的解析表达式.就高度非傍轴情形,进一步给出了简洁的计算公式,在高斯光源线度趋向零的极限情形下,横向的最大发散角为90°.同时,还推广到了傍轴情形,得到了与原有傍轴公式稍有区别的结果,而且光束传输因子始终保持略大于1最后,对非傍轴矢量高斯光束和非傍轴标量高斯光束的传输进行了比较,结果显示对于线度在两个波长范围之内的高斯光源发散
关键词:
矢量高斯光束
光束传输
非傍轴
二阶矩 相似文献
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The explicit far-field expressions for the TE and TM terms and energy flux distributions of electromagnetic elliptical Gaussian vortex beams are derived and their far-field properties including the phase singularities and energy flux distributions of the TE and TM terms and whole beam are studied in detail. It is shown that there exist two edge dislocations. The number and position of edge dislocations and energy flux distributions are dependent on the amplitude ratio and waist width ratio of electromagnetic elliptical Gaussian vortex beams. The analytical results are illustrated numerically. 相似文献
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PU Jixiong 《Chinese Journal of Lasers》2001,10(3):228-232
1 Introduction Recentlytherehasbeenconsiderableinterestindesignandanalysisofthediffractiveaxiconsthatproduceafocalsegmentwithnearlyuniformopticalintensityalongthesystemaxiswithinaspecifiedregionbehindtheelement[1~1 2 ] .Thisisduetotheirunusualpropertiesa… 相似文献