Studies towards Acceleration of Relativistic Electron Beamsin Laser-driven Dielectric Microstructures

2020 
In this work an approach to relativistic electron acceleration employing laser-driven dielectric microstructures (DLA) is considered. New DLA designs were developed, a simulation code for efficient DLA simulation was devised, the capabilities of dielectric microstructures as particle beam diagnostic devices were investigated and a laser induced damage threshold measurement setup was implemented and tested.To leverage well developed near-infrared laser sources new DLAs were designed that are robust against realistic manufacturing tolerances and exhibit a predicted increased electron transmission of up to \SI{44}{\percent} of the charge and longitudinal acceptance of around \SI{2}{\femto\second}, but are still able to produce \SI{}{\giga\volt/\meter} acceleration gradients. A great challenge is the numerical simulation of long interaction lengths of electrons with the short drive laser wavelengths present in DLAs due to the high demand in computation resources needed by the large simulation domain compared to the wavelength. A novel method was developed, which is able to efficiently model meter long DLAs without any resonant particle approximations by use of transfer maps generated from a single-period electromagnetic field simulation and a limited set of particle tracking simulations. In PIC simulations hundreds of DLA periods can be modeled using a high performance computing cluster. With the code presented in this work a meter long DLA (hundred thousands of periods) can be simulated on a workstation. This PhD work includes the numerical investigation of particle beam diagnostics capabilities of DLAs, namely as transverse deflecting structures and as new passive and active bunch length measurement devices for ultra-short particle bunches in the sub-femto second regime. All the presented methods are very compact in the particle beam line compared to existing methods.An experiment was devised to test the designed DLAs by injection of an electron bunch from a conventional state-of-the-art radio frequency accelerator with the potential to show first increase of the average energy of a relativistic electron beam in a DLA device. In contrast all experiments up to today are only modulating the particle beam energy. Finally an experimental setup was designed and implemented to measure the short pulse laser induced damage threshold of DLAs with characterization measurements taken on a bulk material.
    • Correction
    • Source
    • Cite
    • Save
    • Machine Reading By IdeaReader
    0
    References
    0
    Citations
    NaN
    KQI
    []