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ABSTRACT: The scattering of a stochastic electromagnetic plane-wave pulse on a deterministic spherical medium is investigated. An analytical formula for the degree of polarization (DOP) of the scattered field in the far zone is derived. Letting pulse duration T(0) → ∞, our formula can be applied to study the scattering of a stationary stochastic electromagnetic light wave. Numerical results show that the DOP of the far zone field is closely determined by the size of the spherical medium when the incident field is a stochastic electromagnetic plane-wave pulse. This is much different from the case when the incident field is a stationary stochastic electromagnetic light wave, where the DOP of the far zone field is independent of the size of the medium. One may obtain the information of the spherical medium by measuring the scattering-induced changes in the DOP of a stochastic electromagnetic plane-wave pulse.
Journal of the Optical Society of America A 06/2012; 29(6):1078-90. · 1.56 Impact Factor
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ABSTRACT: Based on the propagation theory of partially coherent light in the space-frequency domain, the anomalous spectral behavior
and spectral switches in the far field of partially coherent and polychromatic light diffracted at an aperture are studied.
It is shown that, as compared with spatially fully coherent and polychromatic light whose spectral anomalies are induced only
by aperture diffraction, the spectral anomalies and spectral switches of partially coherent and polychromatic light depend
on the aperture diffraction, spatial correlationβ and bandwidth of the original spectrum. Detailed numerical calculations are made to illustrate the behavior of spectral switches
of partially coherent and polychromatic light, and the results for spatially fully coherent and polychromatic light are treated
as a special case ofβ=1 and included in our theory.
Science in China Series G Physics Mechanics and Astronomy 04/2012; 47(1):24-35. · 1.41 Impact Factor
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ABSTRACT: The scattering of a partially coherent plane-wave pulse on a Gaussian-correlated, quasi-homogeneous random medium is investigated. The analytical expressions for the temporal coherence length and the pulse duration of the scattered field are derived. We demonstrate that the scattering-induced changes in the temporal coherence length and the pulse duration may be used to determine the correlation function of the scattering potential of the medium.
Optics Letters 02/2011; 36(4):517-9. · 3.40 Impact Factor
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ABSTRACT: Phase singularities and spectral changes of spectrally partially coherent higher-order Bessel-Gauss pulsed beams in free-space propagation are studied, and the analytical expressions for the spectral degree of coherence and spectrum are derived. It is shown that there always exists an optical vortex at the center of the beam and the topological charge is conserved during the propagation. Some circular edge dislocations appear and the spectrum changes on propagation. A rapid spectral transition takes place. Numerical illustrative examples are given and the results are explained physically.
Journal of the Optical Society of America A 12/2009; 26(12):2654-61. · 1.56 Impact Factor
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ABSTRACT: We consider the stochastic electromagnetic Gaussian Schell-model (EGSM) beam and show that the polarization of stochastic electromagnetic EGSM beams in the source plane affect spectral switches of diffracted stochastic electromagnetic EGSM beams in the far field. For two cases of fully coherent and partially coherent δ<sub>xx</sub>=δ<sub>yy</sub> the behavior of spectral switches are same in different degrees of polarization of the source.
Applied Physics Letters 12/2009; · 3.84 Impact Factor
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ABSTRACT: Taking the spectrally partially coherent Gaussian Schell-model pulsed (GSMP) beam as a typical example of spatially and spectrally partially coherent pulsed beams, an analytical expression for the spectrum of diffracted spectrally partially coherent GSMP beams propagating through atmospheric turbulence is derived by using the method of the complex Gaussian function expansion, and used to study the spectral switches of spectrally partially coherent GSMP beams in atmospheric turbulence. Numerical calculation results are given to illustrate the dependence of spectral switches on the refraction index structure constant and temporal coherent length. The results are interpreted physically.
Journal of Optics A Pure and Applied Optics 08/2009; 11(10):105404. · 1.92 Impact Factor
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ABSTRACT: The unified theory of coherence and polarization proposed by Wolf is extended from stochastic stationary electromagnetic beams to stochastic spatially and spectrally partially coherent electromagnetic pulsed beams. Taking the stochastic electromagnetic Gaussian Schell-model pulsed (GSMP) beam as a typical example of stochastic spatially and spectrally partially coherent electromagnetic pulsed beams, the expressions for the spectral density, spectral degree of polarization and spectral degree of coherence of stochastic electromagnetic GSMP beams propagating in free space are derived. Some special cases are analyzed. The illustrative examples are given and the results are interpreted physically.
New Journal of Physics 08/2009; 11(8):083001. · 4.18 Impact Factor
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ABSTRACT: Analytical formulas for the cross-spectral density matrix of stochastic electromagnetic Gaussian Schell-model (EGSM) beams passing through an astigmatic optical system are derived. We show both analytically and by numerical examples the effects of astigmatism on spectra, coherence and polarization of stochastic electromagnetic EGSM beams propagating through an astigmatic lens. A comparison with the aberration-free case is made, and shows that the astigmatism has significant effect on the spectra, coherence and polarization.
Optics Express 05/2009; 17(9):7310-21. · 3.59 Impact Factor
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ABSTRACT: The phase singularities and spectral switches of focused higher-order Bessel–Gauss pulsed beams are studied. Numerical calculation results are given to illustrate the dependence of phase singularities and spectral switches of focused higher-order Bessel–Gauss pulsed beams on the truncation parameter, topological charge, spatial parameter and propagation distance. It is shown that there always exists an optical vortex at the center of focused higher-order Bessel–Gauss pulsed beams and the topological charge is conserved during the propagation. The spectral switch appears in the neighborhood of the zero- or minimum-intensity position. With increasing topological charge or spatial parameter, the size of the vortex core increases and the spectral transition height decreases.
Journal of Modern Optics 04/2009; 56(7):863-874. · 1.17 Impact Factor
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ABSTRACT: Taking the Gaussian Schell-model (GSM) beam as a typical example of partially coherent beams, the analytical expressions of the spectrum of GSM beams propagating in dispersive media are derived, and the spectral properties are studied in detail. It is shown that, in comparison with propagation in free space and in turbulence, whether or not GSM beams satisfy the scaling law, the normalized spectrum of GSM beams in dispersive media changes on propagation in general, because the dispersive medium affects different spectral components differently. As compared with the free-space propagation, for the scaling-law GSM beams the dispersion results in spectrum change, and for the nonscaling-law GSM beams the dispersion gives rise to a further increase in spectral changes. The structure constant of the dispersive property of the media, the transverse coordinate of the observation point, the spatial correlation length of the source, and the propagation distance affect the spectral behavior of GSM beams; this effect is illustrated numerically.
Journal of the Optical Society of America A 09/2008; 25(8):2122-8. · 1.56 Impact Factor
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ABSTRACT: Starting from the propagation law of partially coherent polychromatic light in the space-frequency domain, detailed numerical results and physical analysis are given to elucidate spectral changes and spectral switches at the geometrical focal plane of Gaussian Schell-model beams focused by an aperture lens. It is found that, in contrast to the aperture-induced spectral anomalies of spatially fully coherent polychromatic light, for partially coherent polychromatic light aperture diffraction plays an important role in spectral switching, but the truncation parameter, spectral correlation, and bandwidth all affect its spectral behavior.
Journal of the Optical Society of America A 02/2004; 21(1):140-8. · 1.56 Impact Factor
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ABSTRACT: The spectral behavior of spatially coherent polychromatic Hermite-Gaussian (H-G) beams focused by an aperture lens is studied by using the propagation law of the cross-spectral density function. An analytical expression for the spectrum of focused H-G beams is derived, which is related to the original spectrum and spectral modifier, and the spectral modifier is dependent on the truncation parameter, Fresnel number, and position parameter. Detailed numerical results are given to illustrate the spectral anomalies of diffracted H-G beams in the neighborhood of focus.
IEEE Journal of Quantum Electronics 11/2003; · 1.88 Impact Factor
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ABSTRACT: Starting from the propagation equation of partially coherent
light, the spectral switching of Gaussian-Schell model (GSM) beams
passing through an aperture lens is studied. Our detailed theoretical
and numerical results have shown that the spectral switching of GSM
beams is mainly dependent on the truncation parameter, coherence
parameter and Fresnel number. By a suitable choice of the system
parameters, the position, number, and transition amplitude of the
spectral switch can be varied
IEEE Journal of Quantum Electronics 05/2002; · 1.88 Impact Factor
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ABSTRACT: Starting from the propagation law of partially coherent light, the aperture effect on the spectral shift in Young's interference experiment is studied. It is shown that by changing the parameter describing the width and distance of two slits and keeping other parameters of the incident partially coherent light and observation distance fixed, red and blue spectral shifts can occur and the spectrum does not change monotonically as usual. The dependence of the spectral shift on the spatial correlation of the source and observation distance is also illustrated with numerical examples.
Journal of Optics A Pure and Applied Optics 04/2002; 4(3):349. · 1.92 Impact Factor
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ABSTRACT: The spectral switch in Young's two-slit experiment with partially
coherent light is studied based on the propagation law of partially
coherent light. It is shown that, by varying the source correlation,
slit parameter and observation distance, the on-axis spectrum changes
gradually, and the spectral switch can take place, where the spectral
shift exhibits a rapid transition from red to blue shift or vice verse
IEEE Journal of Quantum Electronics 12/2001; · 1.88 Impact Factor
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ABSTRACT: Based on the beam coherent-polarization (BCP) matrix approach and propagation law of partially coherent beams, analytical propagation equations of partially polarized Gaussian Schell-model (PGSM) beams through an astigmatic lens are derived, which enables us to study the propagation-induced polarization changes and irradiance distributions at any propagation distance of PGSM beams through an astigmatic lens within the framework of the paraxial approximation. Detailed numerical results for a PGSM beam passing through an astigmatic lens are presented. A comparison with the aberration-free case is made, and shows that the astigmatism affects the propagation properties of PGSM beams.
Optik - International Journal for Light and Electron Optics 116(10):481-485. · 0.51 Impact Factor
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ABSTRACT: Based on the beam coherence-polarization (BCP) matrix approach and propagation law of partially coherent beams, the propagation of partially polarized Gaussian Schell-model (PGSM) beams through an aperture is studied. Numerical calculation results are given to illustrate the propagation-induced polarization changes and irradiance distribution of PGSM beams for the apertured case.
Optik - International Journal for Light and Electron Optics 113(8):325-328. · 0.51 Impact Factor
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ABSTRACT: Based on the propagation law of partially coherent light, the spectral changes of Gaussian Schell-model beams passing through a dispersive lens are studied, and the material dispersion of first and second order is taken into consideration. As compared with the dispersion-free case, where there is only a blue shift of the on-axis spectrum in the neighborhood of the focus, the first-order dispersion may result in the on-axis spectral splitting, and both blue and red shifts take place near the focus. The second-order dispersion gives rise to a further increase of spectral splitting. The spectral splitting increases as the spatial correlation increases.
Optik - International Journal for Light and Electron Optics 114(11):485-490. · 0.51 Impact Factor
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ABSTRACT: Starting from the Huygens–Fresnel diffraction integral, the recurrence expression for the power spectra of pulsed Hermite–Gaussian beams in Young’s interference experiment in dispersive media are derived and used to study the spectral anomalies of pulsed Hermite–Gaussian beams in the far field. The results of numerical calculation are given to illustrate the dependence of spectral anomalous behavior on the pulse parameter, slit parameter, diffraction angle and dispersive property of medium. The potential application of spectral anomalies of pulsed Hermite–Gaussian beams in information encoding and information transmission in dispersive media is considered.
Optics Communications 281(5):1197-1203. · 1.49 Impact Factor
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ABSTRACT: Starting from the Huygens–Fresnel diffraction integral, the analytical expression for the power spectrum of diffracted pulsed Bessel beams in a dispersive media is derived and used to study the spectral anomalies of pulsed Bessel beams in the far field. Numerical results are given to illustrate the dependence of the anomalous spectral behavior on the pulse parameters, aperture parameter and dispersive properties of the medium. It is shown that, near phase singularities, anomalous spectral behavior may take place. The potential applications of spectral anomalies of ultrashort pulsed beams in information encoding and information transmission are considered.
Optics & Laser Technology 40(2):394-400. · 1.51 Impact Factor
