Schemes for generating ultra-low emittance beams have been developed in the last years with applications, for example, in high-energy physics and free-electron laser science. Current methods for the characterization of low emittance beams such as pepperpot measurements or quadrupole scans are limit to about $e_n\approx0.2\pi$ $mm$ $mrad$. Here we propose a novel method for the characterization of ultra-low emittance beams using structured light fields. In this scheme, two laser pulses are focused under an angle creating a grating-like intensity pattern. When the electron beam interacts with the structured light field, the phase space of the electron beam becomes modulated. By measuring the electron beam profile in the far-field, this method allows the characterization of ultra-low emittance beams. 2D PIC simulations are performed using a parameter range of $e_n=[0.01,1]$ $\pi$ $mm$ $mrad$. We discuss several application scenarios for the characterization of ultra-low emittance beams.
|Working group||Laser-driven electron acceleration|