Helical Electron Beam Micro-Bunching by High-Order Modes in a Micro-Plasma Waveguide

Area of Science:

• Plasma physics
• Laser-plasma interactions
• Particle acceleration

Background:

• Electron acceleration in plasma waveguides is crucial for generating high-energy particle beams.
• Laguerre-Gaussian (LG) laser pulses offer unique properties for controlling laser-plasma interactions.

Purpose of the Study:

• To investigate electron acceleration by high-power LG pulses within a micro-plasma waveguide.
• To demonstrate the generation of helical micro-bunched electron beams with high charge and energy.

Main Methods:

• Utilized 3D particle-in-cell (PIC) simulations to model the interaction.
• Employed circularly polarized LG laser pulses to excite high-order waveguide modes.
• Analyzed electron trajectories and energy gain within the helical electric fields.

Main Results:

• Achieved acceleration of electrons to GeV energies.
• Demonstrated customized helical micro-bunching of electron beams with high charge (100s nC) and low divergence (~2°).
• Observed transverse electron migration enhancing acceleration energy through co-propagation with high-order waveguide modes.

Conclusions:

• High-power LG pulses can generate high-charge, relativistic electron beams with controlled helicity.
• This technique shows potential for advancements in fundamental science and various applications.
• The study highlights a novel pathway for tailored electron beam generation.