On the importance of frequency-dependent beam parameters for vacuum acceleration with few-cycle radially-polarized laser beams

Abstract

Tightly-focused, ultrashort radially-polarized laser beams have a large longitudinal field, which provides a strong motivation for direct particle acceleration and manipulation in vacuum. The broadband nature of these beams means that chromatic properties of propagation and focusing are important to consider. We show via single particle simulations that using the correct frequency-dependent beam parameters is imperative, especially as the pulse duration decreases to the few-cycle regime. The results with different spatio-spectral amplitude profiles show both a drastic increase or decrease of the final accelerated electron energy depending on the shape, motivating both proper characterization and potentially a route to optimization.

arXiv comment5 pages, 4 figures

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Cited by in corpus (5)

• Roadmap on spatiotemporal light fields
• Focused fields of ultrashort radially-polarized laser pulses having low-order spatio-temporal couplings
• Coupling to multi-mode waveguides with space-time shaped free-space pulses
• General laws of the propagation of ultrafast vortices in free space
• Ultrashort laser pulses with chromatic astigmatism