Atomic photoexcitation as a tool for probing purity of twisted light modes
Abstract
The twisted light modes used in modern atomic physics experiments can be contaminated by small admixtures of plane-wave radiation. Although these admixtures hardly reveal themselves in the beam-intensity profile, they may seriously affect the outcome of high-precision spectroscopy measurements. In the present study we propose a method for diagnosing such a plane-wave contamination which is based on the analysis of the magnetic sublevel population of atoms or ions interacting with the "twisted + plane-wave" radiation. In order to theoretically investigate the sublevel populations, we solve the Liouville-von Neumann equation for the time evolution of the atomic density matrix. The proposed method is illustrated for the electric dipole 5 s 1/2 2S -5 p 3/2 2P transition in Rb induced by (linearly, radially, or azimuthally polarized) vortex light with just a small contamination. We find that even tiny admixtures of plane-wave radiation can lead to remarkable variations in the populations of the ground-state magnetic sublevels. This opens up new opportunities for diagnostics of twisted light in atomic spectroscopy experiments.
- Publication:
-
Physical Review A
- Pub Date:
- March 2024
- DOI:
- 10.1103/PhysRevA.109.033103
- arXiv:
- arXiv:2310.10197
- Bibcode:
- 2024PhRvA.109c3103S
- Keywords:
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- Physics - Atomic Physics;
- Quantum Physics
- E-Print:
- 12 pages, 11 figures