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Localization of angular momentum in optical waves propagating through turbulence
Darryl J Sanchez1, Denis W Oesch
1Starfire Optical Range, AFRL/RDS, Kirtland AFB, Albuquerque, NM, USA. AFRL/RDSWorkflowOrgMailbox@Kirtland.af.mil
Optics Express
|January 26, 2012
Summary
Atmospheric turbulence can create orbital angular momentum in light beams. This study shows that this angular momentum is a normal and localized effect of light propagation through turbulence.
Area of Science:
- Optics and Photonics
- Atmospheric Physics
Background:
- Orbital angular momentum (OAM) in light is a fundamental property with applications in optical communications and microscopy.
- The effect of atmospheric turbulence on the OAM of light beams is not fully understood.
- Previous studies have primarily focused on the degradation of OAM, not its creation.
Purpose of the Study:
- To demonstrate the creation of non-trivial orbital angular momentum in optical beams propagating through atmospheric turbulence.
- To investigate the localization and characteristics of turbulence-induced OAM.
- To establish OAM creation as a normal phenomenon during light propagation in turbulent media.
Main Methods:
- Controlled laboratory experiments simulating atmospheric turbulence.
- Propagation of laser beams through a turbulent medium.
- Analysis of beam properties to detect and quantify induced angular momentum.
Main Results:
- Demonstrated that atmospheric turbulence can impart significant orbital angular momentum to light beams.
- Showed that the induced angular momentum is highly localized within the beam.
- Confirmed that OAM creation is an inherent aspect of light propagation through turbulence.
Conclusions:
- Atmospheric turbulence is capable of generating orbital angular momentum in optical waves.
- The induced OAM is a localized phenomenon, not a global beam property.
- This finding opens new avenues for understanding light-matter interactions in complex media and potential applications.
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