In the present analysis, we study the dynamics of charged particles submitted to the action of slowly modulated electromagnetic carrier waves. While the velocity of the particles remains smaller than the carrier's phase-velocity, their dynamics is well described by a refined ponderomotive approach. The ponderomotive approach has its own validity limits well established, beyond which particles are resonantly trapped by the carrier waves. We show that under adequate conditions, the trapping mechanism places particles at an optimal relative phase with respect to the carrier for maximum acceleration. In addition to the analytical approach involved in the ponderomotive description, we use numerical simulations to validate the corresponding dynamics as well as to explore various features of the resonant trapping and acceleration. Published by AIP Publishing.
We propose to use ultrahigh intensity laser pulses with wave-front rotation (WFR) to produce short, ultraintense surface plasma waves (SPW) on grating targets for electron acceleration. Combining a smart grating design with optimal WFR conditions identified through simple analytical modeling and particle-in-cell simulation allows us to decrease the SPW duration (down to a few optical cycles) and increase its peak amplitude. In the relativistic regime, for Iλ 2 0 = 3.4 × 10 19 W/cm 2 μm 2 , such SPW are found to accelerate high charge (few 10 s of pC), high energy (up to 70 MeV), and ultrashort (few fs) electron bunches.
Articles you may be interested inRelativistic solutions for one-and two-dimensional space-charge limited current in coaxial diode Phys. Plasmas 20, 053103 (2013) A fully kinetic model for the electron flow in a crossed field device is derived and used to determine the system stationary states. It is found that for low injection temperatures, there is a simultaneous presence of distinct stationary solutions and an abrupt transition between accelerating and space-charge limited regimes. On the other hand, for high injection temperatures, there is only a single stationary solution branch and the change between the regimes becomes continuous. For intermediate temperatures, it is then identified a critical point that separates the abrupt and continuous behaviors. It is also investigated how intrinsic space-charge oscillations may drive stationary states unstable in certain parameter regimes. The results are verified with N-particle self-consistent simulations. V C 2014 AIP Publishing LLC. [http://dx
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.