Complete spatiotemporal and polarization characterization of ultrafast vector beams

TL;DR

This paper presents a novel technique for full spatiotemporal and polarization characterization of ultrafast vector beams, enabling detailed analysis of complex light waveforms with evolving polarization at femtosecond and micrometer scales.

Contribution

It introduces a compact interferometric method for comprehensive measurement of structured ultrafast vector beams with high resolution in space, time, and polarization.

Findings

Successfully measured radially polarized and complex-shaped beams.

Confirmed polarization evolution at micrometer and femtosecond scales.

Demonstrated potential for optimizing applications in ultrafast optics.

Abstract

The use of structured ultrashort pulses with coupled spatiotemporal properties is emerging as a key tool for ultrafast manipulation. Ultrafast vector beams are opening exciting opportunities in different fields such as microscopy, time-resolved imaging, nonlinear optics, particle acceleration or attosecond science. Here, we implement a technique for the full characterization of structured time-dependent polarization light waveforms with spatiotemporal resolution, using a compact twofold spectral interferometer, based on in-line bulk interferometry and fibre-optic coupler assisted interferometry. We measure structured infrared femtosecond vector beams, including radially polarized beams and complex-shaped beams exhibiting both temporal and spatial evolving polarization. Our measurements confirm that light waveforms with polarization evolving at the micrometer and femtosecond scales can be achieved through the use of structured waveplates and polarization gates. This new scale of measurement achieved will open the way to predict, check and optimize applications of structured vector beams at the femtosecond and micrometer scales.