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Title: Synthesis and observation of non-Abelian gauge fields in real space
Particles placed inside an Abelian (commutative) gauge field can acquire different phases when traveling along the same path in opposite directions, as is evident from the Aharonov-Bohm effect. Such behaviors can get significantly enriched for a non-Abelian gauge field, where even the ordering of different paths cannot be switched. So far, real-space realizations of gauge fields have been limited to Abelian ones. We report an experimental synthesis of non-Abelian gauge fields in real space and the observation of the non-Abelian Aharonov-Bohm effect with classical waves and classical fluxes. On the basis of optical mode degeneracy, we break time-reversal symmetry in different manners, via temporal modulation and the Faraday effect, to synthesize tunable non-Abelian gauge fields. The Sagnac interference of two final states, obtained by reversely ordered path integrals, demonstrates the noncommutativity of the gauge fields. Our work introduces real-space building blocks for non-Abelian gauge fields, relevant for classical and quantum exotic topological phenomena.  more » « less
Award ID(s):
1838412
PAR ID:
10190067
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
Science
Volume:
365
Issue:
6457
ISSN:
0036-8075
Page Range / eLocation ID:
1021 to 1025
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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