Charged particle beam transport in a flying focus pulse with orbital angular momentum

Abstract

We demonstrate the capability of Flying Focus (FF) laser pulses with $\ell =1$ orbital angular momentum (OAM) to transversely confine ultra-relativistic charged particle bunches over macroscopic distances while maintaining a tight bunch radius. A FF pulse with $\ell =1$ OAM creates a radial ponderomotive barrier that constrains the transverse motion of particles and travels with the bunch over extended distances. As compared to freely propagating bunches, which quickly diverge due to their initial momentum spread, the particles co-traveling with the ponderomotive barrier slowly oscillate around the laser pulse axis within the spot size of the pulse. This can be achieved at FF pulse energies that are orders of magnitude lower than required by Gaussian or Bessel pulses with OAM. The ponderomotive trapping is further enhanced by radiative cooling of the bunch resulting from rapid oscillations of the charged particles in the laser field. This cooling decreases the mean square radius and emittance of the bunch during propagation.

17 pages, 9 figures

References in corpus (6)

• Advances in QED with intense background fields
• Diffraction-free space-time beams
• Radiation Reaction Effects on Radiation Pressure Acceleration
• Spatiotemporal control of laser intensity through cross-phase modulation
• Exact solutions for the electromagnetic fields of a flying focus
• Creation and direct laser acceleration of positrons in a single stage

Cited by in corpus (3)

• Signatures of vacuum birefringence in low-power flying focus pulses
• High-charge relativistic electrons by vacuum laser acceleration from plasma mirrors using flying focus pulses
• Enhanced quantum radiation with flying-focus laser pulses