Propagation Properties of Gaussian Schell-Model Beam Array in the Jet Engine Exhaust Induced Turbulence

Abstract

The effects of the jet engine turbulence on a Gaussian Schell-Model (GSM) beam array propagating in a jet engine plume are studied theoretically. The analytical expressions of the cross-spectral density (CSD) function, the spectral degree of coherence (DOC) and the mean-squared beam width for a GSM beam array propagating through a jet engine plume region are derived based on the extended Huyens-Fresnel integral. It is found that the profile of spectral density and the DOC of a GSM beam array gradually transfer to an elliptical shape as the propagation distance increases, and the elliptical degree becomes greater with increasing source coherence length. Besides, as the source coherence length decreases, the effect of the jet engine turbulence on the beam broadening is smaller and the profile of the DOC appears sidelobes at short distance. It is also found that the values of effective coherence width nearly remain the same for different values of source coherence length after propagating a certain distance. Furthermore, the effects of the number of beamlets on the beam width and effective coherence width are investigated in detail.

Radial phased-locked Laguerre-Gaussian correlated schell-model beam array

“…When a radial PL LGCSM beam array propagates through free space, the CSD of this beam array can be written by the extended Huygens-Fresnel principle [ 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 ]. with , and is the wavelength.…”

“…Partially coherent beams (PCBs) have widely been researched due to their advantages in turbulence [ 5 ], and models of beam array composed of PCBs are introduced. The properties of the beam array composed of the Gaussian Schell-model (GSM) beams are analyzed [ 6 , 7 , 8 , 9 , 10 , 11 ]. In addition, new models of beam array are also introduced, such as random arrays [ 12 ], twist GSM array beams [ 13 ], radial phased-locked (PL) Lorentz beam array [ 14 ], radial PL rotating elliptical Gaussian beam array [ 15 ], radial PL partially coherent standard Hermite-Gaussian beam [ 16 ], radial PL partially coherent anomalous hollow beam array [ 17 ], radial PL partially coherent elegant Laguerre–Gaussian beam array [ 18 ], PL radially-polarized vector fields array [ 19 ], radial PL multi-GSM beam array [ 20 ], and rotating anisotropic GSM array beams [ 21 ].…”

Coherent beam combining as a multidisciplinary education and training environment

“…The fundamental disciplinary for a coherently combined laser system is optics and photonics, which involves the knowledge from classical courses such as laser principles, laser technology and physical optics. In addition, in order to optimize the performance, the knowledge from mechanical engineering [3] and atmosphere physics [4] are encouraged to be mastered, and thus the comprehension of the results of coherent beam combining for practical use can be enhanced simultaneously.…”

Propagation Characteristics of a Partially Coherent Gaussian Schell‐model Array Vortex Beam in the Joint Turbulence Effect of a Jet Engine and Atmosphere

“…Lately, there has been increased interest in examining the propagation of some optical beams in jet engine exhaust. [ 42–49 ] When a laser beam is emitted from a source and propagates through both jet engine‐induced turbulence and atmospheric turbulence before reaching a target, the beam will certainly be affected by the turbulence, and that will degrade its quality, which will have a negative impact on the accuracy and precision of the laser system. Meanwhile, the combined effect of jet and atmospheric turbulence on the propagation of airborne partially coherent array beams has been investigated by.…”