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arXiv · 2303.13420

Intra-Pulse Intensity Noise Shaping by Saturable Absorbers

Marvin Edelmann·Mikhail Pergament·Franz X. Kärtner
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Abstract

In this work, we identify and characterize intra-pulse intensity noise shaping by saturable absorbers applied in mode-locked lasers and ultra-low noise nonlinear fiber amplifiers. Reshaped intra-pulse intensity noise distributions are shown to be inevitably interconnected with self-amplitude modulation, the fundamental physical mechanism for initiation and stabilization of ultra-short pulses in the steady-state of a mode-locked laser. A theoretical model is used to describe the ultrafast saturation dynamics by an intra-pulse noise transfer function for widely-applied slow and fast saturable absorbers. For experimental verification of the theoretical results, spectrally-resolved relative intensity noise measurements are applied on chirped input pulses to enable the direct measurement of intra-pulse noise transfer functions using a versatile experimental platform. It is further demonstrated, how the characterized intra-pulse intensity noise distribution of ultrafast laser systems can be utilized for quantum-limited intensity noise suppression via tailored optical bandpass filtering.

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Marvin Edelmann, Mikhail Pergament, Franz X. Kärtner. 2023-03-23. Intra-Pulse Intensity Noise Shaping by Saturable Absorbers. https://arxiv.org/abs/2303.13420

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