Effect of source anisotropy on the intensity correlations of stochastic electromagnetic beams in free space communications

Yıl 2024, Cilt: 30 Sayı: 1, 31 - 35, 29.02.2024

Serkan Şahin

Öz

Correlations between stochastic electromagnetic beams' intensity variations which are produced by sources with anisotropic cross-spectral density matrices are explored. Recently introduced spectral degree of cross-polarization, spectral degree of coherence, and the intensity fluctuations of electromagnetic sources are analyzed upon propagation by considering the source as an anisotropic beam. An analytical formula is given for the cross-spectral density matrix of an anisotropic electromagnetic Gaussian Schell beam moving across free space and extended to longitudinal and transverse directions. The analysis shows that the cross-polarization of two beams having same source parameters might increase or decrease on propagation depending on the anisotropy ratio α. Numerical results are presented to show that the beam anisotropy might be one of the convenient methods for modeling partially coherent sources.

Anahtar Kelimeler

Optical communications, Partial coherence, Physical optics, Electromagnetic waves

Kaynak anizotropisinin serbest uzay iletişimde stokastik elektromanyetik ışınların yoğunluk korelasyonları üzerindeki etkisi

Öz

Anizotropik çapraz spektral yoğunluk matrislerine sahip kaynaklar tarafından üretilen stokastik elektromanyetik ışınların yoğunluk değişimleri arasındaki korelasyonlar araştırıldı. Geçtiğimiz yıllarda tanıtılan spektral çapraz polarizasyon derecesi, spektral tutarlılık derecesi ve elektromanyetik kaynakların yayılma üzerine yoğunluk dalgalanmaları, kaynağı bir anizotropik ışın olarak ele alarak analiz edildi. Boş uzayda ilerleyen ve boyuna ve enine yönlere uzanan bir anizotropik elektromanyetik Gauss Schell ışınının çapraz spektral yoğunluk matrisi için analitik bir formül verilmiştir. Analiz, aynı kaynak parametrelerine sahip iki ışının çapraz polarizasyonunun, anizotropi oranı α'ya bağlı olarak yayılma sırasında artabileceğini veya azalabileceğini göstermektedir. Işın anizotropisinin kısmen uyumlu kaynakları modellemek için uygun yöntemlerden biri olabileceğini göstermek için sayısal sonuçlar sunulmuştur.

Anahtar Kelimeler

Optik komünikasyon, Kısmi tutarlılık, Fiziksel optik, Elektromanyetik dalgalar

Kaynakça

• [1] Li Y, Wolf E. “Radiation from anisotropic gaussian schell-model sources”. Optics Letters, 7(6), 256-258, 1982.
• [2] Simon R. “Anisotropic gaussian beams”. Optics Communications, 46(5), 265-269, 1983.
• [3] Shirai T, Wolf E. “Correlations between intensity fluctuations in stochastic electromagnetic beams of any state of coherence and polarization”. Optics Communications, 272(2), 289-292, 2007.
• [4] Volkov SN, James DFV, Shirai T, Wolf E. “Intensity fluctuations and the degree of cross-polarization in stochastic electromagnetic beams”. Journal of Optics A: Pure and Applied Optics, 10(5), 1-4, 2008.
• [5] Al-Qasimi A, Lahiri M, Kuebel D, James DFV, Wolf E. “The influence of the degree of cross-polarization on the hanbury brown-twiss effect”. Optics Express, 18(16), 17124-17129, 2010.
• [6] Zheng S, Huang J, Ji X, Cheng K, Wang T. “Rotating anisotropic Gaussian Schell-model array beams”. Optics Communications, 484, 1-6, 2021.
• [7] Simon R, Mukunda N. "Shape-invariant anisotropic Gaussian Schell-model beams: A complete characterization". Journal of the Optical Society of America A, 15(5), 1361-1370, 1998.
• [8] Cai Y, He S. “Propagation of a partially coherent twisted anisotropic Gaussian Schell-model beam in a turbulent atmosphere”. Applied Physics Letters 89(4), 041117-0411173, 2006.
• [9] Du X, Zhao D, Korotkova O. "Changes in the statistical properties of stochastic anisotropic electromagnetic beams on propagation in the turbulent atmosphere". Optics Express, 15(25), 16909-16915, 2007.
• [10] Liu Y, Zhao Y, Liu X, Liang C, Liu L, Wang F, Cai Y. “Statistical characteristics of a twisted anisotropic gaussian schell‐model beam in turbulent ocean”. Photonics, 7(2), 37-51, 2020.
• [11] Simon R, Sudarshan ECG, Mukunda N. “Anisotropic gaussian schell-model beams: Passage through optical systems and associated invariants”. Physical Review A, 31(4), 2419-2434, 1985.
• [12] Cai Y, Hu L. “Propagation of partially coherent twisted anisotropic Gaussian Schell-model beams through an apertured astigmatic optical system”. Optics Letters, 31(6), 685-687, 2006.
• [13] Wang H, Wang X, Zeng A, Yang K. “Effects of coherence on anisotropic electromagnetic Gaussian Schell model beams on propagation”. Optics letters, 32(15), 2215-2217, 2007.
• [14] Wang H, Wang X, Zeng A, Yang K. “Anisotropic-source-induced changes of the degree of polarization of stochastic electromagnetic beams on propagation”. Journal of Optics A: Pure and Applied Optics, 9(11), 1053-1056, 2007.
• [15] Ellis J, Dogariu A. “Complex degree of mutual polarization”. Optics letters, 29(6), 536-538, 2004.
• [16] Mandel L, Wolf E. Optical Coherence and Quantum Optics, 1st ed. Cambridge, UK, Cambridge University Press, 1995.
• [17] Al-Qasimi A, Korotkova O, James DFV, Wolf E. “Definitions of the degree of polarization of a light beam”. Optics Letters, 32(9), 1015-1016, 2007.
• [18] Lahiri M. “Polarization properties of stochastic light beams in the space-time and space-frequency domains”. Optics Letters, 34(19), 2936-2938, 2009.
• [19] Kuebel D. “Properties of the degree of cross-polarization in the space-time domain”. Optics Communications, 282(17), 3397-3401, 2009.
• [20] Sahin S, Korotkova O, Zhang G, Pu J. “Free space propagation of the spectral degree of cross-polarization of stochastic electromagnetic beams”. Journal of Optics A: Pure and Applied Optics, 11(8), 1-8, 2009.
• [21] Pu J, Korotkova O. “Propagation of the degree of cross-polarization of a stochastic electromagnetic beam through the turbulent atmosphere”. Optics Communications, 282(9), 1691-1698, 2009.
• [22] Singh HK, Kanseri B. “Experimental investigation of degree of cross-polarization for an electromagnetic Gaussian-Schell model beam”. Journal of the Optical Society of America A, 39(12), 98-104, 2022.
• [23] Kanseri B, Joshi D. “Measurement of two-point coherence functions of electromagnetic optical fields and applications of optical coherence”. Asian Journal of Physics, 29(10-12), 649-671, 2020.
• [24] De Santis P, Gori F, Guattari G, Palma C. “Anisotropic gaussian schell-model sources”. Journal of Modern Optics, 33(3), 315-326, 1986.