Chirped-Pulse Forward Raman Amplification in Nonuniform Plasmas
Abstract
Light amplification via Raman scattering in plasma has been severely constrained by stringent phase matching conditions and the need for plasma uniformity. To overcome these limitations, we propose a forward Raman amplification scheme that employs a positively chirped seed pulse co-propagating with a pump pulse in a nonuniform plasma with an upramp density profile. We demonstrate that the phase detuning induced by plasma nonuniformity can be dynamically compensated, enabling broadband amplification across the entire spectral bandwidth of the seed pulse. Concurrently, the chirped pulse duration undergoes continuous compression as a result of the spatially varying dispersion of the plasma. Our theoretical model, incorporating the detuning term and supported by particle-in-cell simulations, elucidates the compensation mechanism. It is shown that a chirped seed pulse with an initial bandwidth ~10% can be directly amplified by a factor of 1e7 to an intensity exceeding 1e17W/cm2 within a picosecond timescale in a steep density ramp. This scheme establishes a new foundation for advancing plasma-based light amplification toward practical applications.
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BibTeX
@misc{lei2026chirpedpulse,
title = {{Chirped-Pulse Forward Raman Amplification in Nonuniform Plasmas}},
author = {Zhi-Yu Lei and Zheng-Ming Sheng and Su-Ming Weng and Min Chen and Jie Zhang},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.02326},
eprint = {2609.02326},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.02326},
note = {CC BY-NC-SA 4.0},
}
RIS
TY - UNPB
TI - Chirped-Pulse Forward Raman Amplification in Nonuniform Plasmas
AU - Zhi-Yu Lei
AU - Zheng-Ming Sheng
AU - Su-Ming Weng
AU - Min Chen
AU - Jie Zhang
PY - 2026
DA - 2026/09/02
PB - arXiv
DO - 10.48550/arxiv.2609.02326
UR - https://arxiv.org/abs/2609.02326
AB - Light amplification via Raman scattering in plasma has been severely constrained by stringent phase matching conditions and the need for plasma uniformity. To overcome these limitations, we propose a forward Raman amplification scheme that employs a positively chirped seed pulse co-propagating with a pump pulse in a nonuniform plasma with an upramp density profile. We demonstrate that the phase detuning induced by plasma nonuniformity can be dynamically compensated, enabling broadband amplification across the entire spectral bandwidth of the seed pulse. Concurrently, the chirped pulse duration undergoes continuous compression as a result of the spatially varying dispersion of the plasma. Our theoretical model, incorporating the detuning term and supported by particle-in-cell simulations, elucidates the compensation mechanism. It is shown that a chirped seed pulse with an initial bandwidth ~10% can be directly amplified by a factor of 1e7 to an intensity exceeding 1e17W/cm2 within a picosecond timescale in a steep density ramp. This scheme establishes a new foundation for advancing plasma-based light amplification toward practical applications.
ER -