Sending femtosecond pulses in circles: highly non-paraxial accelerating beams

TL;DR

This paper demonstrates the generation of highly non-paraxial accelerating beams along a circular arc using femtosecond pulses, achieving the highest transverse acceleration reported, with preserved temporal structure.

Contribution

It introduces a method for creating non-paraxial accelerating beams with circular trajectories that maintain femtosecond pulse integrity, expanding the capabilities of beam shaping.

Findings

Achieved lateral beam movement of 14 μm over 28 μm propagation.

Generated non-paraxial accelerating beams along a 60-degree arc.

Confirmed preservation of femtosecond temporal structure near the caustic.

Abstract

We use caustic beam shaping on 100 fs pulses to experimentally generate non-paraxial accelerating beams along a 60 degree circular arc, moving laterally by 14 \mum over a 28 \mum propagation length. This is the highest degree of transverse acceleration reported to our knowledge. Using diffraction integral theory and numerical beam propagation simulations, we show that circular acceleration trajectories represent a unique class of non-paraxial diffraction-free beam profile which also preserves the femtosecond temporal structure in the vicinity of the caustic.