Angle-Resolved Attosecond Streaking of Twisted Attosecond Pulses

TL;DR

This paper demonstrates how energy- and angle-resolved attosecond streaking can be used to characterize the orbital angular momentum in twisted attosecond pulses, revealing their angular modulations and polarization effects.

Contribution

It introduces a method to determine the OAM content of twisted attosecond pulses using streaking spectroscopy, highlighting the influence of polarization on the spectra.

Findings

Angular modulations in spectra for linearly polarized twisted pulses.

Isotropic spectra for circularly polarized twisted pulses.

Spectra are sensitive to the OAM values and polarization configurations.

Abstract

The present work focuses on the characterisation of the amount of orbital angular momentum (OAM) encoded in the twisted attosecond pulses via energy- and angle-resolved attosecond streaking in pump-probe setup. It is found that the photoelectron spectra generated by the linearly polarised twisted pulse with different OAM values exhibit angular modulations, whereas circularly polarised twisted pulse yields angular isotropic spectra. It is demonstrated that the energy- and angle-resolved streaking spectra are sensitive to the OAM values of the twisted pulse. Moreover, the different combinations of the polarisation of the twisted pump pulse and strong infrared probe pulse influence the streaking spectra differently. The characterisation of the OAM carrying twisted attosecond pulses opens up the possibility to explore helical light-matter interaction on attosecond timescale.