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arXiv · 1802.08906

Multi-frequency Raman amplifiers

Ido Barth·Nathaniel J. Fisch
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Abstract

In its usual implementation, the Raman amplifier features only one pump carrier frequency. However, pulses with well-separated frequencies can also be Raman amplified while compressed in time. Amplification with frequency-separated pumps is shown to hold even in the highly nonlinear, pump-depletion regime, as derived through a fluid model, and demonstrated via particle-in-cell (PIC) simulations. The resulting efficiency is similar to single-frequency amplifiers, but, due to the beat-wave waveform of both the pump lasers and the amplified seed pulses, these amplifiers feature higher seed intensities with a shorter spike duration. Advantageously, these amplifiers also suffer less noise backscattering, because the total fluence is split between the different spectral components.

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BibTeXRIS

Ido Barth, Nathaniel J. Fisch. 2018-02-24. Multi-frequency Raman amplifiers. https://doi.org/10.1103/physreve.97.033201

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