Speaker
Carlos Granados
(Martin-Luther Universität Halle-Wittenberg)
Description
The interaction of spatially tailored laser pulses (such as photonic vortices) with matter is receiving an increasing attention recently. This is mainly due to the possibility of imparting to matter a well defined amount of orbital angular momenta (OAM) which is associated with winding number of the optical vortex [1]. This renders possible non-dipolar transitions or transitions with well defined polarity [2], and provides a new tool to control the spin in spin-orbital coupled systems [3]. Furthermore, appropriately tailored optical vortices result in strong mechanical forces [4].
In this contribution we will consider low-energy electron emission from atoms via vortex beams, particularly Laguerre-Gaussian beams. The low energy electron emission probabilities of atoms in vortex fields are calculated as a function of the OAM of the laser and the position of the target inside the beam. A modified threshold behavior of the corresponding ionization cross sections is found. We will also present and discuss the low-energy photoelectron angular distributions and contrast with recent experimental measurements [5].
[1] L. Allen et al, Phys. Rev. A 45, 8185 (1992)
[2] J. Wätzel and J. Berakdar, Phys. Rev. A 94, 033414 (2016)
[3] K. Köksal and J. Berakdar, Phys. Rev. A 86, 63812 (2012)
[4] D. Schulze et al, Ann. Phys. 529, 1600379 (2017)
[5] T. Kaneyasu et al, Phys. Rev. A 95, 023413 (2017)
Primary authors
Carlos Granados
(Martin-Luther Universität Halle-Wittenberg)
Jamal Berakdar
(Martin-Luther Universität Halle-Wittenberg)
Jonas Wätzel
(Martin-Luther Universität Halle-Wittenberg)
