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Light contains both spin and orbital angular momentum. Despite contributing equally to the total photonic angular momentum, these components derive from quite different parts of the electromagnetic field profile, namely its polarization and spatial variation, respectively, and therefore do not always share equal influence in light–matter interactions. With the growing interest in utilizing light’s orbital angular momentum to practice added control in the study of atomic systems, it becomes increasingly important for students and researchers to understand the subtlety involved in these interactions. In this article, we present a review of the fundamental concepts and recent experiments related to the interaction of beams containing orbital angular momentum with atoms. An emphasis is placed on understanding light’s angular momentum from the perspective of both classical waves and individual photons. We then review the application of these beams in recent experiments, namely single- and few-photon transitions, strong-field ionization, and high-harmonic generation, highlighting the role of light’s orbital angular momentum and the atom’s location within the beam profile within each case.
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Hypergrating for focusing vortex beam below diffraction limit
Light with an orbital angular momentum can strongly modify optical transition selection rules when beam size is reduced to subwavelength scale. We demonstrated a method for focusing orbital angular momentum beams below the diffraction limit
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- Award ID(s):
- 2004298
- PAR ID:
- 10327938
- Date Published:
- Journal Name:
- CLEO 2022
- Page Range / eLocation ID:
- STu5H.4
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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