Browsing by Author "Cai, Yangjian"

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Citation Count: Cai, Y., Korotkova, O., Eyyuboğlu,H.T., Baykal, Y. (2008). Active laser radar systems with stochastic electromagnetic beams in turbulent atmosphere. Optics Express, 16(20), 15834-15846. http://dx.doi.org/10.1364/OE.16.015834
Active laser radar systems with stochastic electromagnetic beams in turbulent atmosphere
(Optical Soc Amer, 2008) Cai, Yangjian; Korotkova, Olga; Eyyuboğlu, Halil T.; Baykal, Yahya; 7688; 7812
Propagation of stochastic electromagnetic beams through paraxial ABCD optical systems operating through turbulent atmosphere is investigated with the help of the ABCD matrices and the generalized Huygens-Fresnel integral. In particular, the analytic formula is derived for the cross-spectral density matrix of an electromagnetic Gaussian Schell-model (EGSM) beam. We applied our analysis for the ABCD system with a single lens located on the propagation path, representing, in a particular case, the unfolded double-pass propagation scenario of active laser radar. Through a number of numerical examples we investigated the effect of local turbulence strength and lens' parameters on spectral, coherence and polarization properties of the EGSM beam
Citation Count: Yuan, Y...et al. (2009). Average intensity and spreading of an elegant Hermite-Gaussian beam in turbulent atmosphere. Optics Express, 17(13), 11130-11139. http://dx.doi.org/10.1364/OE.17.011130
Average intensity and spreading of an elegant Hermite-Gaussian beam in turbulent atmosphere
(Optical Soc Amer, 2009) Yuan, Yangsheng; Cai, Yangjian; Qu, Jun; Eyyuboğlu, Halil T.; Baykal, Yahya; 7688; 7812
The propagation of an elegant Hermite-Gaussian beam (EHGB) in turbulent atmosphere is investigated. Analytical propagation formulae for the average intensity and effective beam size of an EHGB in turbulent atmosphere are derived based on the extended Huygens-Fresnel integral. The corresponding results of a standard Hermite-Gaussian beam (SHGB) in turbulent atmosphere are also derived for the convenience of comparison. The intensity and spreading properties of EHGBs and SHGBs in turbulent atmosphere are studied numerically and comparatively. It is found that the propagation properties of EHGBs and SHGBs are much different from their properties in free space, and the EHGB and SHGB with higher orders are less affected by the turbulence. What's more, the SHGB spreads more rapidly than the EHGB in turbulent atmosphere under the same conditions. Our results will be useful in long-distance free-space optical communications
Citation Count: Wang, F...et al. (2010). Average intensity and spreading of partially coherent standard and elegant Laguerre-Gaussian beams in turbulent atmosphere. Progress In Electromagnetics Research-Pier, 103, 33-56.
Average intensity and spreading of partially coherent standard and elegant Laguerre-Gaussian beams in turbulent atmosphere
(E M W Publishing, 2010) Wang, F.; Cai, Yangjian; Eyyuboğlu, Halil T.; Baykal, Yahya; 7688; 7812
Analytical expressions for the average intensity, mean-squared beam width and angular spread of partially coherent standard and elegant Laguerre-Gaussian (LG) beams propagating in turbulent atmosphere are derived. The properties of the average intensity, spreading and directionality of partially coherent standard and elegant LG beams in turbulent atmosphere are studied numerically and comparatively. It is found that the beam parameters and structure constant of turbulence together determine the properties of the beams in turbulent atmosphere. Partially coherent standard and elegant LG beams with smaller coherence length, larger beam orders and longer wavelength are less affected by the turbulence. A partially coherent elegant LG beam is less affected by turbulence than a partially coherent standard LG beam under the same condition. Furthermore, it is found that there exist equivalent partially coherent standard and elegant LG beams, equivalent fully coherent standard and elegant LG beams, equivalent Gaussian Schell-model beams that may have the same directionality as a fully coherent Gaussian beam both in free space and in turbulent atmosphere. Our results will be useful in long distance free-space optical communications
Citation Count: Cai, Y...et al. (2008). Average irradiance and polarization properties of a radially or azimuthally polarized beam in a turbulent atmosphere. Optics Express, 16(11), 7665-7673. http://dx.doi.org/10.1364/OE.16.007665
Average irradiance and polarization properties of a radially or azimuthally polarized beam in a turbulent atmosphere
(Optical Society of America, 2008) Cai, Yangjian; Qiang, Lin; Eyyuboğlu, Halil T.; Baykal, Yahya; 7688; 7812
Analytical formulas are derived for the average irradiance and the degree of polarization of a radially or azimuthally polarized doughnut beam (PDB) propagating in a turbulent atmosphere by adopting a beam coherence-polarization matrix. It is found that the radial or azimuthal polarization structure of a radially or azimuthally PDB will be destroyed (i.e., a radially or azimuthally PDB is depolarized and becomes a partially polarized beam) and the doughnut beam spot becomes a circularly Gaussian beam spot during propagation in a turbulent atmosphere. The propagation properties are closely related to the parameters of the beam and the structure constant of the atmospheric turbulence
Citation Count: Çil, C.Z...et al. (2009). Beam wander characteristics of cos and cosh-Gaussian beams. Applied Physisc B-Lasers And Optics, 95(4), 763-771. http://dx.doi.org/10.1007/s00340-009-3553-5
Beam wander characteristics of cos and cosh-Gaussian beams
(Springer, 2009) Çil, Celal Zaim; Eyyuboğlu, Halil T.; Baykal, Yahya; Cai, Yangjian; 7688; 7812
Within the context of a general beam formulation, beam wander characteristics of cos and cosh-Gaussian beams are derived and numerically evaluated. In our graphs, the fundamental Gaussian beam is used as a benchmark for comparisons. The associated plots reveal that at small source sizes, a cos-Gaussian beam has the lowest beam wander, while this property is enhanced with increasing values of the displacement parameter. At large source sizes however, this advantage is taken over by cosh-Gaussian beam. Joint examination against the changing source sizes and propagation lengths shows that the range of source sizes, where the beam wander of cos-Gaussian beam remains lower, is enlarged as we go toward higher propagation lengths. Asymmetric beams tend to exhibit higher beam wanders both at small and large source sizes, but for the intermediate source size ranges, the beam wanders of asymmetric beams will fall below those of the symmetric beams. Explanations concerning these behaviors are offered. A historical account of beam wander formulation is also included
Citation Count: Çil, C.Z...et al. (2009). Beam wander of J (0)- and I (0)-Bessel Gaussian beams propagating in turbulent atmosphere. Applied Physisc B-Lasers And Optics, 98(1), 195-202. http://dx.doi.org/10.1007/s00340-009-3724-4
Beam wander of J (0)- and I (0)-Bessel Gaussian beams propagating in turbulent atmosphere
(Springer, 2010) Çil, Celal Zaim; Eyyuboğlu, Halil T.; Baykal, Yahya; Korotkova, Olga; Cai, Yangjian; 7688; 7812
Root mean square (rms) beam wander of J (0)-Bessel Gaussian and I (0)-Bessel Gaussian beams, normalized by the rms beam wander of the fundamental Gaussian beam, is evaluated in atmospheric turbulence. Our formulation is based on the first and the second statistical moments obtained from the Rytov series. It is found that after propagating in atmospheric turbulence, the collimated J (0)-Bessel Gaussian and the I (0)-Bessel Gaussian beams have smaller rms beam wander than that of the Gaussian beam, regardless of the choice of Bessel width parameter. However, the extent of such an advantage depends on the chosen width parameter, Gaussian source size, propagation distance and the wavelength. Focusing at finite distances of the considered beams causes the rms beam wander to decrease sharply at the propagation distances equal to the focusing parameter
Citation Count: Cil, C. Z...et al. "Beam wander of J (0)- and I (0)-Bessel Gaussian beams propagating in turbulent atmosphere",Applied Physıcs B-Lasers and Optics, Vol. 98, No. 1, pp. 195-202, (2010).
Beam Wander of J (0)- and I (0)-Bessel Gaussian Beams Propagating In Turbulent Atmosphere
(Springer, 2010) Çil, Celal Zaim; Eyyuboğlu, Halil T.; Bykal, Yahya; Korotkova, Olga; Cai, Yangjian; 7812; 7688
Root mean square (rms) beam wander of J (0)-Bessel Gaussian and I (0)-Bessel Gaussian beams, normalized by the rms beam wander of the fundamental Gaussian beam, is evaluated in atmospheric turbulence. Our formulation is based on the first and the second statistical moments obtained from the Rytov series. It is found that after propagating in atmospheric turbulence, the collimated J (0)-Bessel Gaussian and the I (0)-Bessel Gaussian beams have smaller rms beam wander than that of the Gaussian beam, regardless of the choice of Bessel width parameter. However, the extent of such an advantage depends on the chosen width parameter, Gaussian source size, propagation distance and the wavelength. Focusing at finite distances of the considered beams causes the rms beam wander to decrease sharply at the propagation distances equal to the focusing parameter.
Citation Count: Eyyuboğlu, Halil T.; Baykal, Y.; Cai, Yangijan, "Complex degree of coherence for partially coherent general beams in atmospheric turbulence", Journal Of The Optical Society Of America A-Optics Image Science And Vision, Vol.24, No.9, pp.2891-2901, (2007).
Complex degree of coherence for partially coherent general beams in atmospheric turbulence
(Optical Soc Amer, 2007) Eyyuboğlu, Halil T.; Baykal, Yahya; Cai, Yangjian; 7688; 7812
With the use of the general beam formulation, the modulus of the complex degree of coherence for partially coherent cosh-Gaussian, cos-Gaussian, Gaussian, annular and higher-order Gaussian optical beams is evaluated in atmospheric turbulence. For different propagation lengths in horizontal atmospheric links, the moduli of the complex degree of coherence at the source and receiver planes are examined when reference points are taken on the receiver axis and off-axis. In the on-axis case, it is observed that in propagation, the moduli of the complex degree of coherence are symmetrical and look like the intensity profile of the related coherent beam propagating in a turbulent atmosphere. For all the beams considered, the moduli of the complex degree of coherence profiles turn into Gaussian shapes beyond certain propagation lengths. In the off-axis case, the moduli of complex degree of coherence patterns become drifted at the earlier propagation lengths. Among the beams investigated, the cos-Gaussian beam is found to be almost independent of the changes in the source partial coherence parameter, and the annular beam seems to be affected the most against the variations of the source partial coherence parameter.
Citation Count: Tong, Z...et al. (2009). Correlation properties of random electromagnetic beams in laser resonators. Applied Physisc B-Lasers And Optics, 97(4), 849-857. http://dx.doi.org/10.1007/s00340-009-3629-2
Correlation properties of random electromagnetic beams in laser resonators
(Springer, 2009) Tong, Z.; Korotkova, Olga; Cai, Yangjian; Eyyuboğlu, Halil T.; Baykal, Yahya; 7688; 7812
With the help of the generalized Huygens-Fresnel principle and the tensor approach for electromagnetic stochastic beams we investigate the behavior of their two-point spatial correlation properties on interaction with a laser resonator. In particular, the evolution of the degree of coherence, of the degree of cross-polarization and of the intensity correlations (at one and two points in space) is analyzed for typical beams and cavities. The theory is illustrated by numerical curves pertaining to various correlation properties of typical electromagnetic Gaussian Schell-model beams
Citation Count: Eyyuboğlu, Halil Tanyer; Baykal, Yahya, "Degree of polarization for partially coherent general beams in turbulent atmosphere", Applied Physics B-Lasers And Optics, Vol.89, No.1, pp.91-97, (2007).
Degree of polarization for partially coherent general beams in turbulent atmosphere
(Springer, 2007) Eyyuboğlu, Halil T.; Baykal, Yahya; Cai, Yangjian; 7688; 7812
The degree of polarization is found for optical excitations of cosh-Gaussian, cos-Gaussian and annular-Gaussian beams in a turbulent atmosphere. The related formulation is based on the beam coherence polarization matrix. The self and mutual coherence functions appearing in the beam coherence polarization matrix are evaluated, when the above mentioned excitations exhibit partial source coherence for self and cross fields. Plots showing the variation of the degree of polarization are provided versus the propagation length when the source size, displacement parameter, structure constant and the degree of source coherence for self and cross fields change.
Citation Count: Wang, Fei...et al. "Diffraction properties of partially coherent elegant high-order beam", Piers 2010 Xi'an: Progress İn Electromagnetics Research Symposium Proceedings, Vols 1 And 2, (2010).
Diffraction properties of partially coherent elegant high-order beam
(Electromagnetics Acad, 2010) Wang, Fei; Cai, Yangjian; Eyyuboğlu, Halil T.; Baykal, Yahya; 7688; 7812
The diffraction properties of a partially coherent elegant higher-order beam in free space are investigated in detail. It is found that the diffraction properties of a partially coherent elegant higher-order beam upon propagation are closely related to its initial coherence. A partially coherent elegant higher-order beam spreads more slowly than a partially coherent standard higher-order beam, which has potential application in free-space optical communications.
Citation Count: Baykal, Yahya; Eyyuboğlu, Hal,l T., "Effect of beam types on the scintillations: A review", Atmospheric Propagation Of Electromagnetic Waves III, Vol.7200, (2009).
Effect of beam types on the scintillations: A review
(Spie-Int Soc Optical Engineering, 2009) Baykal, Yahya; Eyyuboğlu, Halil T.; Cai, Yangjian; 7812; 7688
When different incidences are launched in atmospheric turbulence, it is known that the intensity fluctuations exhibit different characteristics. In this paper we review our work done in the evaluations of the scintillation index of general beam types when such optical beams propagate in horizontal atmospheric links in the weak fluctuations regime. Variation of scintillation indices versus the source and medium parameters are examined for flat-topped-Gaussian, cosh-Gaussian, cos-Gaussian, annular, elliptical Gaussian, circular (i.e., stigmatic) and elliptical (i.e., astigmatic) dark hollow, lowest order Bessel-Gaussian and laser array beams. For flat-topped-Gaussian beam, scintillation is larger than the single Gaussian beam scintillation, when the source sizes are much less than the Fresnel zone but becomes smaller for source sizes much larger than the Fresnel zone. Cosh-Gaussian beam has lower on-axis scintillations at smaller source sizes and longer propagation distances as compared to Gaussian beams where focusing imposes more reduction on the cosh-Gaussian beam scintillations than that of the Gaussian beam. Intensity fluctuations of a cos-Gaussian beam show favorable behaviour against a Gaussian beam at lower propagation lengths. At longer propagation lengths, annular beam becomes advantageous. In focused cases, the scintillation index of annular beam is lower than the scintillation index of Gaussian and cos-Gaussian beams starting at earlier propagation distances. Cos-Gaussian beams are advantages at relatively large source sizes while the reverse is valid for annular beams. Scintillations of a stigmatic or astigmatic dark hollow beam can be smaller when compared to stigmatic or astigmatic Gaussian, annular and flat-topped beams under conditions that are closely related to the beam parameters. Intensity fluctuation of an elliptical Gaussian beam can also be smaller than a circular Gaussian beam depending on the propagation length and the ratio of the beam waist size along the long axis to that along the short axis (i.e., astigmatism). Comparing against the fundamental Gaussian beam on equal source size and equal power basis, it is observed that the scintillation index of the lowest order Bessel-Gaussian beam is lower at large source sizes and large width parameters. However, for excessively large width parameters and beyond certain propagation lengths, the advantage of the lowest order Bessel-Gaussian beam seems to be lost. Compared to Gaussian beam, laser array beam exhibits less scintillations at long propagation ranges and at some midrange radial displacement parameters. When compared among themselves, laser array beams tend to have reduced scintillations for larger number of beamlets, longer wavelengths, midrange radial displacement parameters, intermediate Gaussian source sizes, larger inner scales and smaller outer scales of turbulence. The number of beamlets used does not seem to be so effective in this improvement of the scintillations.
Citation Count: Yuan, Y...et al. (2013). Effect of spatial coherence on the scintillation properties of a dark hollow beam in turbulent atmosphere. Applied Physisc B-Lasers And Optics, 110(4), 519-529. http://dx.doi.org/10.1007/s00340-012-5288-y
Effect of spatial coherence on the scintillation properties of a dark hollow beam in turbulent atmosphere
(Springer, 2013) Yuan, Yangsheng; Chen, Yahong; Liang, Chunhao; Cai, Yangjian; Baykal, Yahya; 7812
With the help of a tensor method, we derive an explicit expression for the on-axis scintillation index of a circular partially coherent dark hollow (DH) beam in weakly turbulent atmosphere. The derived formula can be applied to study the scintillation properties of a partially coherent Gaussian beam and a partially coherent flat-topped (FT) beam. The effect of spatial coherence on the scintillation properties of DH beam, FT beam and Gaussian beam is studied numerically and comparatively. Our results show that the advantage of a DH beam over a FT beam and a Gaussian beam for reducing turbulence-induced scintillation increases particularly at long propagation distances with the decrease of spatial coherence or the increase of the atmospheric turbulence, which will be useful for long-distance free-space optical communications
Citation Count: Yao, M...et al. (2008). Evolution of the degree of polarization of an electromagnetic Gaussian Schell-model. beam in a Gaussian cavity. Optics Letters, 33(19), 2266-2268. http://dx.doi.org/10.1364/OL.33.002266
Evolution of the degree of polarization of an electromagnetic Gaussian Schell-model. beam in a Gaussian cavity
(Optical Soc Amer, 2008) Yao, Min; Cai, Yangjian; Eyyuboğlu, Halil T.; Baykal, Yahya; Korotkova, Olga; 7688; 7812
The interaction of an electromagnetic Gaussian Schell-model (EGSM) beam with a Gaussian cavity is analyzed. In particular, the evolution of the degree of polarization of the EGSM beam is investigated. The results show that the behavior of the degree of polarization depends on both the statistical properties of the source that generates the EGSM beam and the parameter of the cavity
Citation Count: Baykal, Y., Cai, Y., Ji, X. (2012). Field correlations of annular beams in extremely strong turbulence. Optic Communications, 285(21-22), 4171-4174. http://dx.doi.org/10.1016/j.optcom.2012.07.006
Field correlations of annular beams in extremely strong turbulence
(Elsevier Science Bv, 2012) Baykal, Yahya; Cai, Yangjian; Ji, Xiaoling; 7812
The field correlations of annular beams are formulated when the atmosphere assumes extremely strong turbulence. Thicker and larger ring sized annular beams are found to exhibit larger absolute field correlations. For the same transverse distance at the receiver plane, annular beams attain larger field correlations if the transverse distance starts from the receiver origin. Comparisons of the annular beam absolute field correlations in extremely strong turbulence with the no turbulence results show that the absolute field correlation variations follow similar trends, except that the magnitudes of the absolute field correlations are much smaller in extremely strong turbulence and the annular fields become decorrelated at very short transverse distances. When the inner scale of turbulence becomes smaller, the absolute field correlations of the annular beams in extremely strong turbulence become smaller.
Citation Count: Baykal, Y.; Eyyuboğlu, Halil Tanyer; Cai, Y., 'Formulation of scintillations for optical incidence of arbitrary field profile' Pıers 2008 Hangzhou: Progress In Electromagnetics Research Symposium, Vols I And Iı, Proceedings, (2008).
Formulation of scintillations for optical incidence of arbitrary field profile
(Electromagnetics Acad, 2008) Baykal, Yahya; Eyyuboğlu, Halil T.; Cai, Yangjian; 7812; 7688
Scintillation index on the receiver axis is formulated in random medium when an optical source with an arbitrary field profile is employed. To represent the arbitrary source field profile, source is decomposed into pixels and the incident field to form the scintillations is expressed as the superposition of the fields from each pixel area. Thus obtained arbitrary field distribution is then introduced into the weak atmospheric turbulence formulation by using Rytov method. Our result, which is in summa ion and integral forms, reduces correctly to the known scintillation index of a Gaussian beam wave in atmospheric turbulence.
Citation Count: Cai, Y...et al. (2009). Generalized tensor ABCD law for an elliptical Gaussian beam passing through an astigmatic optical system in turbulent atmosphere. Applied Physisc B-Lasers And Optics, 94(2), 319-325. 10.1007/s00340-008-3339-110.1007/s00340-008-3339-1
Generalized tensor ABCD law for an elliptical Gaussian beam passing through an astigmatic optical system in turbulent atmosphere
(Springer, 2009) Cai, Yangjian; Lin, Q.; Eyyuboğlu, Halil T.; Baykal, Yahya; 7688; 7812
The propagation of an elliptical Gaussian beam (EGB) through an astigmatic ABCD optical system in a turbulent atmosphere is investigated. An analytical formula for the average intensity of an EGB and a generalized tensor ABCD law for the generalized complex curvature tensor are derived. As an application example, we derived an analytical formula for the average intensity of an elliptical flat-topped beam propagating through an astigmatic ABCD optical system in a turbulent atmosphere. As a numerical example, the focusing properties of an EGB focused by a thin lens in a turbulent atmosphere are studied. It is found that the focused beam at the focal plane becomes a circular Gaussian beam when the atmospheric turbulence is strong enough, and the beam width of the circular Gaussian beam is determined by atmospheric turbulence strength, focal length of the thin lens, and wavelength of the initial beam but is independent of the initial beam widths (i.e., initial intensity distribution)
Citation Count: Eyyuboğlu, H.T., Cai, Y. (2012). Hypergeometric Gaussian beam and its propagation in turbulence. Optic Communications, 285(21-22), 4194-4199. http://dx.doi.org/10.1016/j.optcom.2012.07.020
Hypergeometric Gaussian beam and its propagation in turbulence
(Elsevier Science Bv, 2012) Eyyuboğlu, Halil T.; Cai, Yangjian; 7688
We study propagation characteristics of hypergeometric Gaussian beam in turbulence. In this context, we formulate the receiver plane intensity using extended Huygens-Fresnel integral. From the graphical results, it is seen that, after propagation, hypergeometric Gaussian will in general assume the shape of a dark hollow beam at topological charges other than zero. Increasing values of topological charge will make the beam broader with steeper walls. On the other hand, higher values of hollowness parameter will contract into a narrower shape. Raising the topological charge or the hollowness parameter individually will cause outer rings to appear. Both increased levels of turbulence and longer propagation distances will accelerate the beam evolution and help reach the final Gaussian shape sooner. At lower wavelengths, there will be less beam spreading
Citation Count: Baykal, Yahya; Eyyuboğlu, Halil Tanyer; Cai, Yangjai, "Incoherent sinusoidal-Gaussian and annular beam scintillations", Fourteenth International Symposium On Atmospheric And Ocean Optics/Atmospheric Physics, Vol.6936, (20089.
Incoherent sinusoidal-Gaussian and annular beam scintillations
(Spie-Int Soc Optical Engineering, 2008) Baykal, Yahya; Eyyuboğlu, Halil T.; Cai, Yangjian; 7812; 7688
The scintillation index is evaluated in horizontal turbulent atmospheric optical links for incidences of incoherent cosh-Gaussian (IChG), cos-Gaussian (ICG) and annular (IA) beams. Weak turbulence solution is obtained for a slow detector. Dependence of the intensity fluctuations of the IChG, ICG and IA beams on the link length, source size, wavelength and the structure constant are examined. At all the link lengths, fixed size IChG and ICG beams exhibit lower scintillations for larger absolute displacement parameters. At a fixed link length, IChG beam yields lower fluctuations than the ICG beam having the same absolute displacement parameter. For the same size primary beams, IA beam with narrower ring scintillates less than the IA beam with wider ring, and this holds to be valid for each link length. Investigation of the scintillation versus the source size reveals that increase in the source size lowers the scintillations for all types of the incoherent beams. At the same source size and the same absolute displacement parameter, IChG beams have lower fluctuations than the ICG beams, larger absolute displacement parameters exhibiting lower scintillations at the same source size for both beams. For IA beams, as the size of the primary beam is increased, the scintillations are reduced for all ring sizes, the reduction being pronounced for narrower rings. As the wavelength increases, the scintillations of IChG and ICG beams first increase, then at around the wavelength forming the Fresnel zone, the scintillations start to decrease and eventually for all types of IChG and ICG beams, the scintillation indices merge towards a certain value. Similar behaviour of the scintillations versus the wavelength is observed for IA beams as well. As long as the structure constant is kept within the range of interest to remain in the weak turbulence, raising the structure constant first increases the intensity fluctuations of beams for all the mentioned beam types where further rises in the structure constant result in the same level of scintillation index. Comparison of the scintillations of IChG, ICG and IA beams with their coherent counterparts and the coherent Gaussian beam shows that the IChG, ICG and IA beams are favorable for large sized sources.
Citation Count: Eyyuboğlu, H.T...et al. (2008). Intensity fluctuations in J-Bessel-Gaussian beams of all orders propagating in turbulent atmosphere. Applied Physisc B-Lasers And Optics, 93(2-3), 605-611. http://dx.doi.org/10.1007/s00340-008-3230-0
Intensity fluctuations in J-Bessel-Gaussian beams of all orders propagating in turbulent atmosphere
(Springer, 2008) Eyyuboğlu, Halil T.; Sermutlu, Emre; Baykal, Yahya; Cai, Yangjian; Korotkova, Olga; 7688; 17647; 7812
The scintillation index of a J (n) -Bessel-Gaussian beam of any order propagating in turbulent atmosphere is derived and numerically evaluated at transverse cross-sections with the aid of a specially designed triple integral routine. The graphical outputs indicate that, just like the previously investigated J (0)-Bessel-Gaussian beam, higher-order members of the family also offer favorable scintillation characteristics at large source sizes. This advantage is maintained against rising beam orders. Viewed along the propagation axis, beams with lower orders and smaller widths exhibit smaller values of the scintillation index at shorter propagation distances and large values at longer propagation distances. Further, it is shown that the scintillation index of the J (n) -Bessel-Gaussian beams (n > 0) is larger than that of the fundamental Gaussian and the J (0)-Bessel-Gaussian beams only near the on-axis points, while remaining smaller towards the edges of the beam