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Propagation factors of multi-sinc Schell-model beams in non-Kolmogorov turbulence

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Abstract

We derive several analytical expressions for the root-mean-square (rms) angular width and the M 2-factor of the multi-sinc Schell-model (MSSM) beams propagating in non-Kolmogorov turbulence with the extended Huygens-Fresnel principle and the second-order moments of the Wigner distribution function. Numerical results show that a MSSM beam with dark-hollow far fields in free space has advantage over the one with flat-topped or multi-rings far fields for reducing the turbulence-induced degradation, which will become more obvious with larger dark-hollow size. Beam quality of MSSM beams can be further improved with longer wavelength and larger beam width, or under the condition of weaker turbulence. We also demonstrate that the non-Kolmogorov turbulence has significantly less effect on the MSSM beams than the Gaussian Schell-model beam.

© 2016 Optical Society of America

1. Introduction

The evolution properties of laser beams on propagation in turbulent atmosphere have been extensively investigated for their significant applications in free-space optical communications and remote sensing [1–9 ]. The random turbulence can inevitably degrade the beam quality. Studies show that partially coherent beams propagating in turbulent atmosphere have substantial advantage over completely coherent beams for reducing turbulence-induced degradation [4–9 ]. Since Gori and his collaborators established a sufficient condition for devising genuine spatial correlation functions [10,11], various partially coherent light sources with non-conventional correlation functions have been proposed and investigated both theoretically and experimentally [12–26 ]. The beam-like fields generated by those sources demonstrate extraordinary propagation characteristics, such as self-focusing and laterally shifted intensity maxima of the non-uniformly correlated (NUC) beams [12–15 ]; tunable flat far-fields of multi-Gaussian Schell-model (MGSM) beams [16, 17] and the first kind sinc Schell-model (SSM1) beams [18], dark-hollow far-fields of Laguerre-Gaussian Schell-model (LGSM) beams [19,20], Bessel-Gaussian Schell-model (BGSM) beams [19], Cosine-Gaussian Schell-model (CGSM) beams [21, 22], and the second kind sinc Schell-model (SSM2) beams [18]; self-splitting properties of Hermite-Gaussian correlated Schell-model (HGCSM) beams [23] and CGSM beams with rectangular symmetry [24, 25], double-layer flat-topped far-fields of electromagnetic sinc Schell-model (EMSSM) beam [26], and so on. The propagation factor (M 2-factor), which can be calculated utilizing the Wigner distribution function (WDF) [27, 28], is regarded as a beam quality factor in many practical applications. Recently, the M 2-factor of several partially coherent beams with nonconventional correlation functions in turbulent atmosphere have been studied [29, 30]. For the modulation of special functions to the degree of coherence, the affection of the turbulence to these beams is less than the conventional GSM beams.

A novel class of partially coherent beams of Schell type named multi-sinc Schell-model (MSSM) beam was recently proposed based on the superposition technique [31]. It demonstrates adjustable multi-rings far-fields in free space. The propagation of MSSM beams in turbulent atmosphere has also been studied [32]. However, to the best of our knowledge, the root-mean-square (rms) angular width and the M 2-factor of MSSM beams propagating in turbulence have not been reported. The main purpose of this paper is to investigate the root-mean-square (rms) angular width and the M 2-factor of MSSM beams on propagation in non-Kolmogorov turbulence. We derive the explicit analytical expressions on propagation based upon the extended Huygens-Fresnel principle and second-order moments of the WDF. The effect of MSSM beams parameters and non-Kolmogorov turbulence on the rms angular width and the M 2-factor in the turbulence are also analyzed by numerical examples. At last, the propagation behaviors of the MSSM beams are compared with that of the conventional GSM beam.

2. Second-order moments of MSSM beams in non-Kolmogorov turbulence

Let us consider a statistically stationary optical field generated by the MSSM source. The cross-spectral density (CSD) function at the source plane z = 0 is expressed as [31, 32]

W0(r1,r2,0)=1Cexp(r12+r222σ2)n=1N(1)n1Bmnsinc(r1r2Bmnδ),
where r 1 and r 2 denotes two points at the input plane, σ represents the beam waist width, δ is the correlation width, Bmn = {(2N − 1)/[2m (2N − 2n + 1)]}1/m is the modified parameter, and the index m is an arbitrary positive real number, C=n=1N(1)n/Bmn is the normalization factor. When N = 1, Eq. (1) reduces to the CSD of the SSM1 beams. When N = 2, Eq. (1) reduces to the CSD of the SSM2 beams.

The paraxial propagation of the CSD of a partially coherent beam through turbulent atmosphere can be treated by the extend Huygens-Fresnel principle. Supposing ρ 1 and ρ 2 are two spatial points at an arbitrary transverse plane of the half-space z = const > 0, the propagation equation of the CSD is described as [33]

W(ρ1,ρ2,z)=(k2πz)2W0(r1,r2,0)exp[ik(ρ1r1)2(ρ2r2)22z]×exp{k2zT2[(ρ1ρ2)2+(ρ1ρ2)(r1r2)+(r1r2)2]}d2r1d2r2,
with
T=2π230κ3Φ(κ,α)dκ,
where k = 2π/λ is the wave number, the term Φ(κ, α) is the spatial power spectrum of the refractive index fluctuations of the turbulent medium, κ is the magnitude of two-dimensional spatial frequency, and α is the power-law exponent. If T = 0, Eq. (2) represents the propagation in free space, and the spectral intensity of MSSM beams at any point (ρ, z) can be obtained as [31]
S(ρ,z)=W(ρ,ρ,z)=δσ2Cω2(z)exp[(ρ+2πzυ/k)2ω2(z)]n=1N(1)n1rect(Bmnδυ)d2υ,
where
ω2(z)=σ2+z2/(k2σ2).

Figure 1 shows the cross line (ρy = 0) of the spectral intensity of MSSM beams with different parameters N and m at propagation distance z = 10km in free space. The other parameters of MSSM beams are chosen to be σ = 0.05m, δ = 0.02m, λ = 632.8nm. It can be easily seen that the far field of MSSM beams with different parameter N demonstrates different profile, such as flat-top profile with N = 1, dark-hollow profile with N = 2, and multi-rings profile with N = 6. Moreover, the dark-hollow size increases with increasing parameter m.

 figure: Fig. 1

Fig. 1 The cross line (ρy = 0) of the spectral intensity of MSSM beams for several values of parameters N and m at propagation distance z = 10km in free space.

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For convenience of the subsequent calculations, the sum and difference vector notation r = (r 1 + r 2)/2, r d = r 1r 2, ρ = (ρ 1 + ρ 2)/2, ρ d = ρ 1ρ 2 are used to rewrite Eq. (2) as follows [34–36 ]

W(ρ,ρd,z)=(k2πz)2W0(r,rd,0)exp[ikz(ρr)(ρdrd)]×exp[k2zT2(ρd2+ρdrd+rd2)]d2rd2rd,

Utilizing the inverse Fourier transform of the Dirac delta function and its property of even function [37], and variable substitution r=r′ and r d = ρ d + z/k ·κ d, the CSD of the MSSM beams at the output plane is expressed as

W(ρ,ρd,z)=(12π)2W0(r,ρd+zkκd,0)expirκdiρκd)×exp[k2zT2(3ρd2+3zkρdκd+z2k2κd2)]d2rd2κd,
where κ d is the position vector in the spatial-frequency domain, and
W0(r,ρd+zkκd,0)=1Cexp[1σ2r214σ2(ρd+zkκd)2]×n=1N(1)n1Bmnsinc[1Bmnδ(ρd+zkκd)].

As is well known, the WDF is very suitable for the treatment of partially coherent beams on propagation in turbulent atmosphere, and it can be expressed as a two-dimensional spatial Fourier transform of the CSD by the following formula [35, 36, 38, 39]

h(ρ,θ,z)=(k2π)2W(ρ,ρd,z)exp(ikθρd)d2ρd,
where vector θ = (θx, θy) denotes an angle which the vector of interest makes with the z-direction, x and y are the wave vector components along the x axis and y axis, respectively.

Substituting Eqs. (7) and (8) into Eq. (9), and calculating the integral with respect to r′ by using the following formula [40]

exp(ax2±bx)dx=πaexp(b24a),(a>0),
the WDF of MSSM beams propagating in turbulent atmosphere is obtained as
h(ρ,θ,z)=k2σ216π3Cexp[σ2κd2414σ2(ρd+zkκd)2]×n=1N(1)n1Bmnsinc[1Bmnδ(ρd+zkκd)]exp(iρκdikθρd)×exp[k2zT2(3ρd2+3zkρdκd+z2k2κd2)]d2κdd2ρd.

The moments of the order of the WDF for three-dimensional beams is defined as [35, 36, 39]

ρxn1ρyn2θxm1θym2=1Pρxn1ρyn2θxm1θym2h(ρ,θ,z)d2ρd2θ,
where P = ∬h(ρ, θ, z)d 2 ρ d 2 θ is the total power of the beams. For a partially coherent Schell beam, the general formulas of the second-order moments of WDF on propagation in turbulent atmosphere can be easily derived as [41, 42]
ρ2=ρ20+θ20z2+2Tz3,
θ2=θ20+6Tz,
ρθ=θ20z+3Tz2,
where θ20=θx20+θy20 and ρ20=ρx20+ρy20 are the second-order moments of WDF at the input plane. Equations (13)(15) imply that the second-order moments of the beams propagating in turbulent atmosphere only relates to the initial second moments, the propagation distance, and the spatial power spectrum of the refractive index fluctuations.

Substituting Eq. (11) into Eq. (12), the second-order moments of WDF of MSSM beams in non-Kolmogorov turbulence at the source plane z = 0 can be obtained as

ρ20=σ2,
θ20=2k21/(2σ2)+n=1N[(1)n1π2]/(Bmn3δ2)n=1N(1)n1/Bmn.

The rms angular width and the M 2-factor are important parameters characterizing light beams. According to the definition of the rms angular width and the M 2-factor of laser beams [28], the analytical expressions of the rms angular width and the M 2-factor of MSSM beams is described as

θN(z)(|θθ|2)1/2=(θ2)1/2={2k21/(2σ2)+n=1N[(1)n1π2]/(Bmn3δ2)n=1N(1)n1/Bmn+6Tz}1/2,
M2(z)=k(ρ2θ2ρθ2)1/2={(2σ2+4Tz3)1/(2σ2)+n=1N[(1)n1π2]/(Bmn3δ2)n=1N(1)n1/Bmn+6k2σ2Tz+3k2T2z4}1/2.
Equations (18) and (19) are used to analyze the statistical properties of MSSM beams on propagation in non-Kolmogorov turbulence. As comparison, a conventional GSM beam is considered in our analysis, and the M 2-factor is given as [35]
MG2(z)=[(2σ2+4Tz3)(12σ2+2δ2)+12k2σ2Tz]1/2.

In this paper, we adopt a generalized power spectrum model, which is valid in non-Kolmogorov turbulence, and its expression is [43, 44]

Φ(κ,α)=A(α)C˜n2exp(κ2/κm2)(κ2+κ02)α/2,0κ<,3<α<4,
where A(α) = (2π)−2Γ(α − 1)cos(απ/2) with Γ(·) is the gamma function, C˜n2 is a index-of-refraction structure constant with units m3− α, κ 0 = 2π/L 0, κm = c(α)/l 0 with c(α) = [2πΓ(5 − α/2) A(α)/3]1/(α−5), L 0 and l 0 are the outer and inner scales of turbulence, respectively. If α = 11/3, L 0 = ∞ and l 0 = 0, Eq. (21) is simplified as follows
Φ(κ,11/3)=0.033Cn2κ11/3,
which represents the ideal Kolmogorov power spectrum. The analytical expression of the strength of non-Kolmogorov turbulence can be obtained by substituting Eq. (21) to Eq. (3), as follows
T=π23(α2)A(α)C˜n2[βκm2αexp(κ02κm2)Γ(2α2,κ02κm2)2κ0(4α)],
where β=(α2)κm2+2κ02, and Γ(·,·) is the incomplete Gamma function.

3. Numerical calculation results and analysis

We now investigate the statistical properties of MSSM beams on propagation in non-Kolmogorov turbulence by numerical simulation. In the following analysis, the calculation parameters of MSSM beams are the same with that used in Fig. 1, and of non-Kolmogorov turbulence are C˜n2=1015m3α, α = 3.1, L 0 = 1m, l 0 = 1mm unless other variable parameters are specified in calculation.

Figure 2 shows the normalized rms angular width of MSSM beams propagating through non-Kolmogorov turbulence for several values of parameters N and m. It can be seen that the normalized rms angular width increases monotonically with the propagation distance. Figure 2(a) indicates that the normalized rms angular width of MSSM beams with the parameter N = 2 is smaller than other values of N when m = 1. While in Fig. 2(b), the normalized rms angular width of MSSM beams decreases with increasing the parameter m when N = 2. It means that the beam with dark-hollow far-fields (N = 2) in free space has stronger resistance to the turbulence than that with flat-topped far-fields (N = 1) and multi-rings far-fields (N = 6), and the resistance increases with the increase of dark-hollow size. The MSSM beams with the parameter N = 2 and larger m are less affected by non-Kolmogorov turbulence from the aspect of the normalized rms angular width.

 figure: Fig. 2

Fig. 2 Normalized rms angular width of MSSM beams propagating through non-Kolmogorov turbulence for several values of (a) parameter N and (b) parameter m, respectively.

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For a partially coherent beam propagating in turbulent atmosphere, the beam quality will be improved with lower spatial coherence. The effect of wavelength λ and beam width σ of MSSM beams on the normalized M 2-factor is considered as follows. Figure 3 shows the dependence of the normalized M 2-factor of the MSSM beams for several values of parameters N and m at propagation distance z = 10km in non-Kolmogorov turbulence on wavelength λ and beam width σ, respectively. One finds that the normalized M 2-factor decreases with increasing wavelength λ or beam width σ. It can be concluded that MSSM beams with longer wavelength or larger beam width are less affected by non-Kolmogorov turbulence.

 figure: Fig. 3

Fig. 3 Normalized M 2-factor of MSSM beams at propagation distance z = 10km in non-Kolmogorov turbulence versus (a) wavelength λ and (b) beam width σ, respectively.

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We will now analyze the influence of non-Kolmogorov turbulence on the propagation factor of MSSM beams. Figure 4 shows the dependence of the normalized M 2-factor of MSSM beams for several values of parameters N and m on the power-law exponent α at propagation distance z = 10km in non-Kolmogorov turbulence. According to Fig. 4, one finds that the normalized M 2-factor of MSSM beams with different parameters N and m reaches the maximum point at the same power-law exponent α = 3.07. When α < 3.07, it increases quickly with the increase of α. When α > 3.07, it decreases gradually with the further increase of α. This result is similar with the dependence of the strength of the non-Kolmogorov turbulence on the power-law exponent α. Therefore, it can be explained that the beam quality is degraded the most at the maximum strength of the turbulence, and improved under the weaker turbulence.

 figure: Fig. 4

Fig. 4 Normalized M 2-factor of MSSM beams versus the power-law exponent α at propagation distance z = 10km in non-Kolmogorov turbulence.

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Figure 5 plots the normalized M 2-factor of MSSM beams for several values of parameters N and m versus the index-of-refraction structure constant C˜n2 at propagation distance z = 10km in non-Kolmogorov turbulence. According to Eq. (23), the strength of the turbulence increases with increasing C˜n2. So it can be seen from Fig. 5 that there is almost no distinct difference for different parameters N and m for weak turbulence. As the strength of the turbulence increases, the normalized M 2-factor of MSSM beams with dark-hollow far-fields (N = 2) in free space is obviously smaller than the one with flat-topped far-fields (N = 1) or multi-rings far-fields (N = 6), and the difference becomes bigger when only increase the parameter m. It can be concluded that a MSSM beam with dark-hollow far-fields in free space has advantage over the one with flat-topped or multi-rings far-fields for reducing the turbulence-induced degradation, and this advantage will become more obvious with larger dark-hollow size.

 figure: Fig. 5

Fig. 5 Normalized M 2-factor of MSSM beams for several values of parameters N and m versus the index-of-refraction structure constant C˜n2 at propagation distance z = 10km in non-Kolmogorov turbulence.

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Figure 6 shows the normalized M 2-factor of the MSSM beams with N = 2 and m = 5 on propagation in non-Kolmogorov turbulence for different power-law exponent α, outer scale L 0, and inner scale l 0. The turbulence with α = 3.1 is stronger than the case α = 3.67. According to Fig. 6, it can be clearly seen that the normalized M 2-factor of MSSM beams is not sensitive to the change of outer scale L 0, especially in stronger turbulence. And at a fixed propagation distance z, MSSM beams are less affected by the turbulence with smaller outer scale L 0 or larger inner scale l 0.

 figure: Fig. 6

Fig. 6 Normalized M 2-factor of the MSSM beams with N = 2 and m = 5 on propagation in non-Kolmogorov turbulence for different power-law exponent α, outer scale L 0, and inner scale l 0.

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Figure 7 shows the difference between the normalized M 2-factor of MSSM beams and a conventional GSM beam on propagation in non-Kolmogorov turbulence. One finds that the normalized M 2-factor of the conventional GSM beam is obviously larger than that of MSSM beams. That is to say, the affection of non-Kolmogorov turbulence to MSSM beams compared to the conventional GSM beam is significantly less. The results presented in this paper might be useful in free-space optical communications.

 figure: Fig. 7

Fig. 7 Normalized M 2-factor of the MSSM beams for several values of parameters N and m on propagation in non-Kolmogorov turbulence compared with the case of GSM beam.

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4. Conclusion

We have derived the analytical expressions of the rms angular width and the M 2-factor of MSSM beams in non-Kolmogorov turbulence by utilizing the extended Huygens-Fresnel principle and second-order moments of the WDF. The effect of beams parameters and non-Kolmogorov turbulence on the normalized rms angular width and the normalized M 2-factor have been investigated in detail. Numerical results have been shown that a MSSM beam with dark-hollow far-fields in free space has advantage over the one with flat-topped or multi-rings far-fields for reducing the turbulence-induced degradation. Such an advantage will become more obvious with larger dark-hollow size. Beam quality of MSSM beams can be further improved with longer wavelength and larger beam width. The effect of non-Kolmogorov turbulence on the normalized M 2-factor of MSSM beams has also been studied. The MSSM beams will be less affected under the condition of weaker turbulence, such as larger power-law exponent α and outer scale L 0 or smaller index-of-refraction structure constant C˜n2 and inner scale l 0. In addition, compared with the conventional GSM beam, the effect of non-Kolmogorov turbulence on MSSM beams is significantly less. Our results will have potential application in free-space optical communications.

Acknowledgments

This work was supported by the National Basic Research Program of China under Grant No. 2013CBA01702, and the National Natural Science Foundation of China under Grant NOs. 11104049, 10974039, 61377016, 61308017, 61575053 and 61575055, and the Fundamental Research Funds for the Central Universities (No. HIT.BRETIII.201406) and the Program for New Century Excellent Talents in University (NCET-12-0148).

References and links

1. L. Mandel and E. Wolf, Optical Coherence and Quantum Optics (Cambridge University, 1995). [CrossRef]  

2. Y. Cai and S. He, “Propagation of various dark hollow beams in a turbulent atmosphere,” Opt. Express 14(4), 1353–1367 (2006). [CrossRef]   [PubMed]  

3. Y. Cai and S. He, “Average intensity and spreading of an elliptical Gaussian beam propagating in a turbulent atmosphere,” Opt. Lett. 31(5), 568–570 (2006). [CrossRef]   [PubMed]  

4. J. C. Ricklin and F. M. Davidson, “Atmospheric turbulence effects on a partially coherent Gaussian beam: implications for free-space laser communication,” J. Opt. Soc. Am. A 19(9), 1794–1802 (2002). [CrossRef]  

5. J. C. Ricklin and F. M. Davidson, “Atmospheric optical communication with a Gaussian Schell beam,” J. Opt. Soc. Am. A 20(5), 856–866 (2003). [CrossRef]  

6. A. Dogariu and S. Amarande, “Propagation of partially coherent beams: turbulence-induced degradation,” Opt. Lett. 28(1), 10–12 (2003). [CrossRef]   [PubMed]  

7. Y. Cai and S. He, “Propagation of a partially coherent twisted anisotropic Gaussian Schell-model beam in a turbulent atmosphere,” Appl. Phys. Lett. 89, 041117 (2006). [CrossRef]  

8. G. Gbur and E. Wolf, “Spreading of partially coherent beams in random media,” J. Opt. Soc. Am. A 19(8), 1592–1598 (2002). [CrossRef]  

9. T. Shirai, A. Dogariu, and E. Wolf, “Mode analysis of spreading of partially coherent beams propagating through atmospheric turbulence,” J. Opt. Soc. Am. A 20(6), 1094–1102 (2003). [CrossRef]  

10. F. Gori and M. Santarsiero, “Devising genuine spatial correlation functions,” Opt. Lett. 32(24), 3531–3533 (2007). [CrossRef]   [PubMed]  

11. F. Gori, V. Remríez-Sánchez, M. Santarsiero, and T. Shirai, “On genuine cross-spectral density matrices,” J. Opt. A: Pure Appl. Opt. 11, 085706 (2009). [CrossRef]  

12. H. Lajunen and T. Saastamoinen, “Propagation characteristics of partially coherent beams with spatially varying correlations,” Opt. Lett. 36(20), 4104–4106 (2011). [CrossRef]   [PubMed]  

13. H. Lajunen and T. Saastamoinen, “Non-uniformly correlated partially coherent pulses,” Opt. Express 21(1), 190–195 (2013). [CrossRef]   [PubMed]  

14. Z. Mei, “Light sources generating self-focusing beams of variable focal length,” Opt. Lett. 39(2), 347–350 (2014). [CrossRef]   [PubMed]  

15. Z. Song, Z. Liu, K. Zhou, Q. Sun, and S. Liu, “Propagation characteristics of a non-uniformly Hermite-Gaussian correlated beam,” J. Opt. 18, 015606 (2016). [CrossRef]  

16. O. Korotkova, S. Sahin, and E. Shchepakina, “Multi-Gaussian Schell-model beams,” J. Opt. Soc. Am. A 29(10), 2159–2164 (2012). [CrossRef]  

17. Z. Mei, O. Korotkova, and E. Shchepakina, “Electromagnetic multi-Gaussian Schell-model beams,” J. Opt. 15, 025705 (2013). [CrossRef]  

18. Z. Mei, “Two types of sinc Schell-model beams and their propagation characteristics,” Opt. Lett. 39(14), 4188–4191 (2014). [CrossRef]   [PubMed]  

19. Z. Mei and O. Korotkova, “Random sources generating ring-shaped beams,” Opt. Lett. 38(2), 91–93 (2013). [CrossRef]   [PubMed]  

20. Y. Chen, L. Liu, F. Wang, C. Zhao, and Y. Cai, “Elliptical Laguerre-Gaussian correlated Schell-model beam,” Opt. Express 22(11), 13975–13987 (2014). [CrossRef]   [PubMed]  

21. Z. Mei and O. Korotkova, “Cosine-Gaussian Schell-model sources,” Opt. Lett. 38(14), 2578–2580 (2013). [CrossRef]   [PubMed]  

22. Z. Mei and O. Korotkova, “Electromagnetic cosine-Gaussian Schell-model beams in free space and atmospheric turbulence,” Opt. Express 21(22), 27246–27259 (2013). [CrossRef]   [PubMed]  

23. Y. Chen, J. Gu, F. Wang, and Y. Cai, “Self-splitting properties of a Hermite-Gaussian correlated Schell-model beam,” Phys. Rev. A 91, 013823 (2015). [CrossRef]  

24. C. Liang, F. Wang, X. Liu, Y. Cai, and O. Korotkova, “Experimental generation of cosine-Gaussian-correlated Schell-model beams with rectangular symmetry,” Opt. Lett. 39(4), 769–772 (2014). [CrossRef]   [PubMed]  

25. Z. Mei, “Light sources generating self-splitting beams and their propagation in non-Kolmogorov turbulence,” Opt. Express 22(11), 13029–13040 (2014). [CrossRef]   [PubMed]  

26. Z. Mei and Y. Mao, “Electromagnetic sinc Schell-model beams and their statistical properties,” Opt. Express 22(19), 22534–22546 (2014). [CrossRef]   [PubMed]  

27. M. J. Bastiaans, “Application of the Wigner distribution function to partially coherent light,” J. Opt. Soc. Am. A 3(8), 1227–1238 (1986). [CrossRef]  

28. J. Serna, R. Martínez-Herrero, and P. M. Mejías, “Parametric characterization of general partially coherent beams propagating through ABCD optical systems,” J. Opt. Soc. Am. A 8(7), 1094–1098 (1991). [CrossRef]  

29. H. Xu, Z. Zhang, J. Qu, and W. Huang, “Propagation factors of cosine-Gaussian-correlated Schell-model beams in non-Kolmogorov turbulence,” Opt. Express 22(19), 22479–22489 (2014). [CrossRef]   [PubMed]  

30. X. Wang, M. Yao, Z. Qiu, X. Yi, and Z. Liu, “Evolution properties of Bessel-Gaussian Schell-model beams in non-Kolmogorov turbulence,” Opt. Express 23(10), 12508–12523 (2015). [CrossRef]   [PubMed]  

31. Z. Mei and O. Korotkova, “Alternating series of cross-spectral densities,” Opt. Lett. 40(11), 2473–2476 (2015). [CrossRef]   [PubMed]  

32. Z. Mei and Y. Mao, “Multi-sinc Schell-model beams and the interaction with a linear random medium,” Laser Phys. Lett. 12, 095002 (2015). [CrossRef]  

33. E. Shchepakina and O. Korotkova, “Second-order statistics of stochastic electromagnetic beams propagating through non-Kolmogorov turbulence,” Opt. Express 18(10), 10650–10658 (2010). [CrossRef]   [PubMed]  

34. L. C. Andrews and R. L. Phillips, Laser Beam Propagation through Random Media, 2nd ed. (SPIE, 2005). [CrossRef]  

35. Y. Dan and B. Zhang, “Beam propagation factor of partially coherent flat-topped beams in a turbulent atmosphere,” Opt. Express 16(20), 15563–15575 (2008). [CrossRef]   [PubMed]  

36. Y. Yuan, Y. Cai, J. Qu, H. T. Eyyuboğlu, Y. Baykal, and O. Korotkova, “M2-factor of coherent and partially coherent dark hollow beams propagating in turbulent atmosphere,” Opt. Express 17(20), 17344–17356 (2009). [CrossRef]   [PubMed]  

37. R. N. Bracewell, The Fourier Transform and Its Applications, 3rd ed. (McGraw-Hill, 2000).

38. S. Du, Y. Yuan, C. Liang, and Y. Cai, “Second-order moments of a multi-Gaussian Schell-model beam in a turbulent atmosphere,” Opt. Laser Technol. 50, 14–19 (2013). [CrossRef]  

39. R. Chen, L. Liu, S. Zhu, G. Wu, F. Wang, and Y. Cai, “Statistical properties of a Laguerre-Gaussian Schell-model beam in turbulent atmosphere,” Opt. Express 22(2), 1871–1883 (2014). [CrossRef]   [PubMed]  

40. I. S. Gradshteyn and I. M. Ryzhik, Table of Integrals, Series, and Products, 7th ed. (Academic, 2007).

41. Y. Dan and B. Zhang, “Second moments of partially coherent beams in atmospheric turbulence,” Opt. Lett. 34(5), 563–565 (2009). [CrossRef]   [PubMed]  

42. Y. Huang, Z. Gao, and B. Zhang, “Propagation properties based on second-order moments for correlated combination partially coherent Hermite-Gaussian linear array beams in non-Kolmogorov turbulence,” J. Mod. Opt. 60(10), 841–850 (2013). [CrossRef]  

43. I. Toselli, L. C. Andrews, R. L. Phillips, and V. Ferrero, “Free-space optical system performance for laser beam propagation through non-Kolmogorov turbulence,” Opt. Eng. 47, 026003 (2008). [CrossRef]  

44. I. Toselli, L. C. Andrews, R. L. Phillips, and V. Ferrero, “Angle of arrival fluctuations for free space laser beam propagation through non-Kolmogorov turbulence,” Proc. SPIE 6551, 65510E (2007). [CrossRef]  

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Figures (7)

Fig. 1
Fig. 1 The cross line (ρy = 0) of the spectral intensity of MSSM beams for several values of parameters N and m at propagation distance z = 10km in free space.
Fig. 2
Fig. 2 Normalized rms angular width of MSSM beams propagating through non-Kolmogorov turbulence for several values of (a) parameter N and (b) parameter m, respectively.
Fig. 3
Fig. 3 Normalized M 2-factor of MSSM beams at propagation distance z = 10km in non-Kolmogorov turbulence versus (a) wavelength λ and (b) beam width σ, respectively.
Fig. 4
Fig. 4 Normalized M 2-factor of MSSM beams versus the power-law exponent α at propagation distance z = 10km in non-Kolmogorov turbulence.
Fig. 5
Fig. 5 Normalized M 2-factor of MSSM beams for several values of parameters N and m versus the index-of-refraction structure constant C ˜ n 2 at propagation distance z = 10km in non-Kolmogorov turbulence.
Fig. 6
Fig. 6 Normalized M 2-factor of the MSSM beams with N = 2 and m = 5 on propagation in non-Kolmogorov turbulence for different power-law exponent α, outer scale L 0, and inner scale l 0.
Fig. 7
Fig. 7 Normalized M 2-factor of the MSSM beams for several values of parameters N and m on propagation in non-Kolmogorov turbulence compared with the case of GSM beam.

Equations (23)

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W 0 ( r 1 , r 2 , 0 ) = 1 C exp ( r 1 2 + r 2 2 2 σ 2 ) n = 1 N ( 1 ) n 1 B m n sinc ( r 1 r 2 B m n δ ) ,
W ( ρ 1 , ρ 2 , z ) = ( k 2 π z ) 2 W 0 ( r 1 , r 2 , 0 ) exp [ i k ( ρ 1 r 1 ) 2 ( ρ 2 r 2 ) 2 2 z ] × exp { k 2 z T 2 [ ( ρ 1 ρ 2 ) 2 + ( ρ 1 ρ 2 ) ( r 1 r 2 ) + ( r 1 r 2 ) 2 ] } d 2 r 1 d 2 r 2 ,
T = 2 π 2 3 0 κ 3 Φ ( κ , α ) d κ ,
S ( ρ , z ) = W ( ρ , ρ , z ) = δ σ 2 C ω 2 ( z ) exp [ ( ρ + 2 π z υ / k ) 2 ω 2 ( z ) ] n = 1 N ( 1 ) n 1 rect ( B m n δ υ ) d 2 υ ,
ω 2 ( z ) = σ 2 + z 2 / ( k 2 σ 2 ) .
W ( ρ , ρ d , z ) = ( k 2 π z ) 2 W 0 ( r , r d , 0 ) exp [ i k z ( ρ r ) ( ρ d r d ) ] × exp [ k 2 z T 2 ( ρ d 2 + ρ d r d + r d 2 ) ] d 2 r d 2 r d ,
W ( ρ , ρ d , z ) = ( 1 2 π ) 2 W 0 ( r , ρ d + z k κ d , 0 ) exp i r κ d i ρ κ d ) × exp [ k 2 z T 2 ( 3 ρ d 2 + 3 z k ρ d κ d + z 2 k 2 κ d 2 ) ] d 2 r d 2 κ d ,
W 0 ( r , ρ d + z k κ d , 0 ) = 1 C exp [ 1 σ 2 r 2 1 4 σ 2 ( ρ d + z k κ d ) 2 ] × n = 1 N ( 1 ) n 1 B m n sinc [ 1 B m n δ ( ρ d + z k κ d ) ] .
h ( ρ , θ , z ) = ( k 2 π ) 2 W ( ρ , ρ d , z ) exp ( i k θ ρ d ) d 2 ρ d ,
exp ( a x 2 ± b x ) d x = π a exp ( b 2 4 a ) , ( a > 0 ) ,
h ( ρ , θ , z ) = k 2 σ 2 16 π 3 C exp [ σ 2 κ d 2 4 1 4 σ 2 ( ρ d + z k κ d ) 2 ] × n = 1 N ( 1 ) n 1 B m n sinc [ 1 B m n δ ( ρ d + z k κ d ) ] exp ( i ρ κ d i k θ ρ d ) × exp [ k 2 z T 2 ( 3 ρ d 2 + 3 z k ρ d κ d + z 2 k 2 κ d 2 ) ] d 2 κ d d 2 ρ d .
ρ x n 1 ρ y n 2 θ x m 1 θ y m 2 = 1 P ρ x n 1 ρ y n 2 θ x m 1 θ y m 2 h ( ρ , θ , z ) d 2 ρ d 2 θ ,
ρ 2 = ρ 2 0 + θ 2 0 z 2 + 2 T z 3 ,
θ 2 = θ 2 0 + 6 T z ,
ρ θ = θ 2 0 z + 3 T z 2 ,
ρ 2 0 = σ 2 ,
θ 2 0 = 2 k 2 1 / ( 2 σ 2 ) + n = 1 N [ ( 1 ) n 1 π 2 ] / ( B m n 3 δ 2 ) n = 1 N ( 1 ) n 1 / B m n .
θ N ( z ) ( | θ θ | 2 ) 1 / 2 = ( θ 2 ) 1 / 2 = { 2 k 2 1 / ( 2 σ 2 ) + n = 1 N [ ( 1 ) n 1 π 2 ] / ( B m n 3 δ 2 ) n = 1 N ( 1 ) n 1 / B m n + 6 T z } 1 / 2 ,
M 2 ( z ) = k ( ρ 2 θ 2 ρ θ 2 ) 1 / 2 = { ( 2 σ 2 + 4 T z 3 ) 1 / ( 2 σ 2 ) + n = 1 N [ ( 1 ) n 1 π 2 ] / ( B m n 3 δ 2 ) n = 1 N ( 1 ) n 1 / B m n + 6 k 2 σ 2 T z + 3 k 2 T 2 z 4 } 1 / 2 .
M G 2 ( z ) = [ ( 2 σ 2 + 4 T z 3 ) ( 1 2 σ 2 + 2 δ 2 ) + 12 k 2 σ 2 T z ] 1 / 2 .
Φ ( κ , α ) = A ( α ) C ˜ n 2 exp ( κ 2 / κ m 2 ) ( κ 2 + κ 0 2 ) α / 2 , 0 κ < , 3 < α < 4 ,
Φ ( κ , 11 / 3 ) = 0.033 C n 2 κ 11 / 3 ,
T = π 2 3 ( α 2 ) A ( α ) C ˜ n 2 [ β κ m 2 α exp ( κ 0 2 κ m 2 ) Γ ( 2 α 2 , κ 0 2 κ m 2 ) 2 κ 0 ( 4 α ) ] ,
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