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Updated: Aug 5, 2025
07:56
A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
8.5K
Nonlinear up-conversion of a polarization Möbius strip with half-integer optical angular momentum
Martin Luttmann1, Mekha Vimal1, Matthieu Guer1,2
1Université Paris-Saclay, CEA, CNRS, LIDYL, Gif-sur-Yvette 91191, France.
Science Advances
|March 24, 2023
Summary
Generalized angular momentum (GAM) is shown to be a valid quantum number for light fields with nontrivial topology. This study demonstrates linear scaling of GAM with harmonic order in high harmonic generation, enabling finer control of light beams.
Area of Science:
- Nonlinear optics
- Quantum optics
- Topological photonics
Background:
- Symmetries and conservation laws are fundamental in nonlinear optics.
- Paraxial light fields with nontrivial topology are of recent interest.
- These fields are eigenstates of generalized angular momentum (GAM), not orbital (OAM) or spin angular momentum (SAM).
Purpose of the Study:
- To investigate the role of GAM in high harmonic generation (HHG).
- To demonstrate the linear scaling of GAM with harmonic order.
- To establish GAM as a relevant quantum number for specific light fields.
Main Methods:
- Driving HHG with a polarization Möbius strip.
- Using a half-integer GAM charge.
- Implementing angular momentum characterization in the extreme ultraviolet (XUV) range.
Main Results:
- Demonstrated linear scaling of GAM with harmonic order.
- Confirmed each harmonic carries a precise half-integer GAM charge.
- Showcased GAM as an appropriate quantum number beyond SAM and OAM.
Conclusions:
- GAM is a crucial quantum number for light fields with fractional polarization singularities.
- This finding enables finer manipulation and application of such light beams.
- Highlights the importance of GAM in understanding topological light fields.
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