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arXiv · 1602.06640

High-Multipole Excitations of Hydrogen-Like Atoms by Twisted Photons near Phase Singularity

Andrei Afanasev·Carl E. Carlson·Asmita Mukherjee
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Abstract

We calculate transition amplitudes and cross sections for excitation of hydrogen-like atoms by the twisted photon states, or photon states with angular momentum projection on the direction of propagation exceeding $\hbar$. If the target atom is located at distances of the order of atomic size near the phase singularity in the vortex center, the transitions rates into the states with orbital angular momentum $l_f>1$ become comparable with the rates for electric dipole transitions. It is shown that when the transition rates are normalized to the local photon flux, the resulting cross sections for $l_f>1$ are singular near the optical vortex center. Relation to the "quantum core" concept introduced by Berry and Dennis is discussed.

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Andrei Afanasev, Carl E. Carlson, Asmita Mukherjee. 2016-04-12. High-Multipole Excitations of Hydrogen-Like Atoms by Twisted Photons near Phase Singularity. https://doi.org/10.1088/2040-8978%2F18%2F7%2F074013

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