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Title: Einstein beams carrying orbital angular momentum
Einstein beams are coherent optical beams generated by the conditions of gravitational lensing. In the ray picture, Einstein beams are formed by the intersection of light rays deflected by a lensing mass, similar to nondiffracting Bessel beams, but with the difference that adjacent rays diverge slightly. When accounting for the wave properties of light, they form beam-like diffraction patterns that preserve their shape but expand as the light propagates. The addition of a topological charge to the light, leads to more complex patterns carrying orbital angular momentum. For symmetric lensing conditions, Einstein beams carry modes described by confluent hypergeometric functions, which can be approximated by Bessel functions. A theoretical analysis of this is presented here. In astrophysical observations, many of these features can only be inferred because conditions of coherence and alignment make them difficult to observe. Studies of Einstein beams in the laboratory can be used to inform astrophysical observations and discover new non-astrophysical laboratory applications.  more » « less
Award ID(s):
2011937
NSF-PAR ID:
10428779
Author(s) / Creator(s):
; ; ; ;
Editor(s):
Andrews, D; Galvez, E; Rubinsztein-Dunlop
Date Published:
Journal Name:
Proceedings of SPIE
Volume:
12436
ISSN:
1996-756X
Page Range / eLocation ID:
124360C
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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