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arXiv · 2404.10280

Efficient diffraction control using a tunable active-Raman gain medium

Sandeep Sharma
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Abstract

We present a new scheme to create all-optical tunable and lossless waveguide using a controllable coherent Raman process in an atomic rubidium vapor in N-type configuration. We employ a Gaussian Raman field and a Laguerre-Gaussian control field to imprint a high-contrast tunable waveguide-like feature inside the atomic medium. We numerically demonstrate that such a waveguide is able to guide arbitrary modes of a weak probe beam to several Rayleigh length without diffraction and absorption. Our results on all-optical waveguide based scheme may have potential application in lossless image processing, high contrast biomedical imaging and image metrology.

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Sandeep Sharma. 2024-04-16. Efficient diffraction control using a tunable active-Raman gain medium. https://doi.org/10.1103/physreva.107.023701

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