Plasma-based ion acceleration
Laser-driven plasma-based accelerators can sustain acceleration gradients that are many orders of magnitude larger than those achievable in conventional accelerators. The acceleration distance can thus be reduced correspondingly, and plasma-based accelerators can be made extremely compact. Our project is focused on the development of laser-plasma based ion sources to bring them closer to applications. The main objective is to increase the efficiency, energy and beam quality of these sources. To achieve this advanced simulations of laser-matter interactions need to be performed and new parameter regimes have to be explored. In the context of numerical simulations of laser-target interactions, the Particle-In-Cell (PIC) approach is one of the most efficient tools for theoretical analysis and predictive estimates. In the most general case the method involves the solution of the equations of motion coupled to Maxwell’s equations. Supercomputer simulations with the PIC approach make it possible to carry out numerical experiments with realistic temporal- and spatial-scales that are in good agreement with experimental data, providing researchers with many opportunities for solving applied and fundamental problems. In this project we will perform simulations for proton acceleration in a micro-sized plasma waveguide (MPW). Such a structure provides modifications to the electromagnetic (EM) wave, and the laser fields can be described as waveguide modes, which are different from the plane waves that are usually assumed. Therefore the interaction between the laser and electrons exhibit many new features that may lead to promising novel schemes and potential applications in the future. This setup has been used by members of our group to propose a novel compact bright X-ray source [L Yi et al, Phys. Rev. Lett. 116, 115001 (2016), https://doi.org/10.1103/PhysRevLett.116.115001 ]. The modification of EM waves by a MPW can be controlled via changing the channel radius and length, and this offers ways to manipulate the laser plasma interaction process. In this project we will study electron transport in the MPW and the energy transfer when the electrons leave the MPW, which in turn affects the ion acceleration process. We will explore the parameter dependence of this setup to provide guidance for future experiments.