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DOE OSTI · 1755147

Evolution of the self-injection process in long wavelength infrared laser driven LWFA

Kumar, Prabhat·Yu, Kwangmin·Zgadzaj, Rafal·Downer, Michael·Petrushina, Irina·Samulyak, Roman·Litvinenko, Vladimir·Vafaei-Najafabadi, Navid
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Abstract

In this work, long wavelength infrared laser-driven plasma wakefield accelerators are investigated in the self-modulated laser wakefield acceleration (SM-LWFA) and blowout regimes using 3D particle-in-cell simulations. The simulation results show that in the SM-LWFA regime, self-injection arises with wave breaking, whereas in the blowout regime, self-injection is not observed under the simulation conditions. The wave breaking process in the SM-LWFA regime occurs at a field strength that is significantly below the 1D wave-breaking threshold. This process intensifies at higher laser power and plasma density and is suppressed at low plasma densities (≤1×10 17 cm –3 here). The produced electrons show spatial modulations with a period matching that of the laser wavelength, which is a clear signature of direct laser acceleration.

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97 MATHEMATICS AND COMPUTINGLasersParticle-in-cell methodPlasma accelerationPlasma properties and parametersPlasma waves

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Kumar, Prabhat, Yu, Kwangmin, Zgadzaj, Rafal, Downer, Michael, Petrushina, Irina, Samulyak, Roman, Litvinenko, Vladimir, Vafaei-Najafabadi, Navid. 2021-01-06. Evolution of the self-injection process in long wavelength infrared laser driven LWFA. https://doi.org/10.1063/5.0027167

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