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arXiv · 1911.00649

Deep learning of ultrafast pulses with a multimode fiber

Wen Xiong·Brandon Redding·Shai Gertler·Yaron Bromberg·Hemant Tagare·Hui Cao
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Abstract

Characterizing ultrashort optical pulses has always been a critical but difficult task, which has a broad range of applications. We propose and demonstrate a self-referenced method of characterizing ultrafast pulses with a multimode fiber. The linear and nonlinear speckle patterns formed at the distal end of a multimode fiber are used to recover the spectral amplitude and phase of an unknown pulse. We deploy a deep learning algorithm for phase recovery. The diversity of spatial and spectral modes in a multimode fiber removes any ambiguity in the sign of the recovered spectral phase. Our technique allows for single-shot pulse characterization in a simple experimental setup. This work reveals the potential of multimode fibers as a versatile and multi-functional platform for optical sensing.

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Wen Xiong, Brandon Redding, Shai Gertler, Yaron Bromberg, Hemant Tagare, Hui Cao. 2019-11-02. Deep learning of ultrafast pulses with a multimode fiber. https://arxiv.org/abs/1911.00649

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