Fig. 1: Diagram of NSDI and the resulting entanglement of OAM.
From: Entanglement of orbital angular momentum in non-sequential double ionization
a Orientation of the linearly polarized laser, with polarization e∣∣ along the z axis taken for the OAM denoted by \({\hat{L}}_{\parallel }\) and the target atom. b NSDI process depicted for the EI and RESI mechanisms. Interaction via the field (e.g. tunnel ionization) is depicted by a dashed line, excitation in the singly charged ion is denoted by dotted lines, while the recollision and OAM sharing is denoted by the yellow spark. The two electron states are defined in the text, following the convention of ref. 66. c The excitation pathways in RESI, which lead to different final OAM states and an entangled superposition. The final states are given by OAM states, \(\left|{l}_{{{{{{{{\rm{e}}}}}}}}},-{l}_{{{{{{{{\rm{e}}}}}}}}}\right\rangle\) as used in (8). The dashed-dotted lines are to denote, which two-electron state the first electron ends up in. The numbers −1, 0, 1 refer to the values of the quantum magnetic number mη of the intermediate excited state, \(\left|\tilde{{{{{{{{\bf{p}}}}}}}}},\, \eta \right\rangle\).
