Changes in the spectrum, in the spectral degree of polarization, and in the spectral degree of coherence of a partially coherent beam propagating through a gradient-index fiber

The intensity distribution of a partially coherent beam with a nonconventional correlation function, named the multi-Gaussian Schell-model (MGSM) beam, focused by an axicon was investigated in detail. Our numerical results showed that an optical needle with a flat-topped spatial profile and long focal depth was formed and that we can modulate the focal shift and focal depth of the optical needle by varying the width of the degree of coherence (DOC) and the parameters of the correlation function. The adjustable optical needle can be applied for electron acceleration, particle trapping, fiber coupling and percussion drilling.

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Generation of an Adjustable Optical Cage through Focusing an Apertured Bessel-Gaussian Correlated Schell-Model Beam

Applied Sciences ◽

10.3390/app9030550 ◽

2019 ◽

Vol 9 (3) ◽

pp. 550 ◽

Cited By ~ 2

Author(s):

Lina Guo ◽

Li Chen ◽

Rong Lin ◽

Minghui Zhang ◽

Yaru Gao ◽

...

Keyword(s):

Thermal Processing ◽

Gaussian Function ◽

Spatial Coherence ◽

Analytical Formula ◽

Coherent Beam ◽

Beam Size ◽

Degree Of Coherence ◽

Spectral Degree ◽

Coherence Width ◽

Effective Beam

An adjustable optical cage generated by focusing a partially coherent beam with nonconventional correlation function named the Bessel–Gaussian correlated Schell-model (BGCSM) beam is investigated in detail. With the help of the generalized Huygens–Fresnel integral and complex Gaussian function expansion, the analytical formula of the BGCSM beam passing through an apertured ABCD optical system was derived. Our numerical results show that the generated optical cage can be moderately adjusted by the aperture radius, the spatial coherence width, and the parameter β of the BGCSM beam. Furthermore, the effect of these parameters on the effective beam size and the spectral degree of coherence were also analyzed. The optical cage with adjustable size can be applied for particle trapping and material thermal processing.

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Generation and Propagation of a Hermite-Gaussian Correlated Schell-Model LG0l Beam

Applied Sciences ◽

10.3390/app9030610 ◽

2019 ◽

Vol 9 (3) ◽

pp. 610 ◽

Cited By ~ 2

Author(s):

Xiaofeng Peng ◽

Xingyuan Lu ◽

Xianlong Liu ◽

Chenliang Zhao ◽

Rong Lin ◽

...

Keyword(s):

Coherence Length ◽

Coherent Beam ◽

Statistical Properties ◽

Vortex Phase ◽

Partially Coherent ◽

Degree Of Coherence ◽

Combined Action ◽

Coherence Width

A partially coherent beam under the combined action of a Hermite-Gaussian correlated function and vortex phase, named the HGCSMLG0l beam has been explored both theoretically and experimentally. The statistical properties, such as the intensity and distribution of the degree of coherence (DOC) on propagation are analyzed in detail, based on the deduced equations. We find that the intensity is determined dominantly by the non-conventional correlated function when the coherence length is comparatively small and by vortex phase when the coherence length is large. The modulus of the DOC is not vulnerable to coherence width, rather, it is affected by both non-conventional correlated function and vortex phase. Our results are verified well by the experiment results.

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