Propagation of Gaussian Schell-model beams in modulated graded-index media

The evolution of partially coherent beams in longitudinally modulated graded-index media is studied. The special cases of Gaussian Schell-model beams and parametric modulation, when the modulation period is half the fiber self-imaging period, are examined in detail. We show that the widths of the intensity and coherence of Gaussian Schell-model beams undergo amplification in parametrically modulated parabolic graded-index media. The process is an analog of quantum mechanical parametric amplification and generation of squeezed states. Our work may find application in spatial and temporal imaging of partially coherent beams in fiber-based imaging systems. (C) 2021 Optical Society of America under the terms of the OSA Open Access Publishing Agreement

Automated summary

This study investigates the evolution of partially coherent beams in longitudinally modulated graded-index media, focusing on the cases of Gaussian Schell-model beams and parametric modulation with a half fiber self-imaging period. It is shown that in parametrically modulated parabolic graded-index media, the widths of intensity and coherence of Gaussian Schell-model beams undergo amplification. This process is analogous to quantum mechanical parametric amplification and generation of squeezed states, and may have applications in spatial and temporal imaging of partially coherent beams in fiber-based imaging systems.