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Title: Determining the Orbital Angular Momentum of a Vortex Beam Using Strong Field Ionization
While interferometric methods exist for classifying vortex states of light, these techniques usually require destroying the beam of interest to determine the light’s OAM. A recent two-color pump-probe experiment employed strong field ionization and beam sculpting to classify vortex beams. Here, we propose an alternative strong-field method for distinguishing OAM states of light which does not require beam sculpting and instead utilizes a noncollinear terahertz standing wave to probe ionized electrons. We then use classical trajectory Monte Carlo (CTMC) methods to simulate strong-field ionization of helium under this configuration with the terahertz field both on and off. We find that the resulting electron momenta distributions can be used to extract the OAM of the beam, as long as the vortex beam spot size does not exceed 1/4 the terahertz pulse’s wavelength.  more » « less
Award ID(s):
2208040
PAR ID:
10498010
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
MDPI
Date Published:
Journal Name:
Photonics
Volume:
10
Issue:
12
ISSN:
2304-6732
Page Range / eLocation ID:
1322
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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