Controlling multiple filaments by relativistic optical vortex beams in plasmas

Area of Science:

• Plasma Physics
• Nonlinear Optics
• Beam Propagation

Background:

• Laser-plasma interactions are crucial for many applications.
• Filamentation instability limits beam propagation distances.
• Optical vortex beams (OVBs) offer unique properties.

Purpose of the Study:

• Investigate the filamentation dynamics of relativistic OVBs in underdense plasma.
• Compare OVB propagation robustness to Gaussian beams.
• Analyze the effect of orbital angular momentum (OAM) on instability.

Main Methods:

• Theoretical investigation of relativistic OVBs.
• Analysis of azimuthal modulational instability growth rates.
• Comparison with standard Gaussian beam propagation.

Main Results:

• OVBs exhibit significantly more robust propagation than Gaussian beams.
• Increasing OVB topological charge rapidly decreases instability growth rate.
• OVBs maintain profiles longer before filamentation.
• OVBs break into regular filament patterns due to OAM conservation.

Conclusions:

• Relativistic OVBs offer superior propagation stability in plasma.
• OAM is key to controlling filamentation and achieving structured beam breakup.
• OVBs present a promising alternative to Gaussian beams for long-distance plasma propagation.