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arXiv · 1801.05241

Laser wakefield acceleration with mid-IR laser pulses

D. Woodbury·L. Feder·V. Shumakova·C. Gollner·R. Schwartz·B. Miao·F. Salehi·A. Korolov·A. Pugžlys·A. Baltuška·H. M. Milchberg
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Abstract

We report on the first results of laser plasma wakefield acceleration driven by ultrashort mid-infrared laser pulses (\lambda= 3.9 \mu m, 100 fs, 0.25 TW), which enable near- and above-critical density interactions with moderate-density gas jets. Relativistic electron acceleration up to ~12 MeV occurs when the jet width exceeds the threshold scale length for relativistic self-focusing. We present scaling trends in the accelerated beam profiles, charge and spectra, which are supported by particle-in-cell simulations and time-resolved images of the interaction. For similarly scaled conditions, we observe significant increases in accelerated charge compared to previous experiments with near-infrared (\lambda=800 nm) pulses.

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D. Woodbury, L. Feder, V. Shumakova, C. Gollner, R. Schwartz, B. Miao, F. Salehi, A. Korolov, A. Pugžlys, A. Baltuška, H. M. Milchberg. 2018-01-16. Laser wakefield acceleration with mid-IR laser pulses. https://doi.org/10.1364/ol.43.001131

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