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Title: Weakly nonlinear topological gap solitons in Su–Schrieffer–Heeger photonic lattices

We study both theoretically and experimentally the effect of nonlinearity on topologically protected linear interface modes in a photonic Su–Schrieffer–Heeger (SSH) lattice. It is shown that under either focusing or defocusing nonlinearity, this linear topological mode of the SSH lattice turns into a family of topological gap solitons. These solitons are stable. However, they exhibit only a low amplitude and power and are thus weakly nonlinear, even when the bandgap of the SSH lattice is wide. As a consequence, if the initial beam has modest or high power, it will either delocalize, or evolve into a soliton not belonging to the family of topological gap solitons. These theoretical predictions are observed in our experiments with optically induced SSH-type photorefractive lattices.

 
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Award ID(s):
1910282
NSF-PAR ID:
10202807
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
Optical Society of America
Date Published:
Journal Name:
Optics Letters
Volume:
45
Issue:
23
ISSN:
0146-9592; OPLEDP
Format(s):
Medium: X Size: Article No. 6466
Size(s):
Article No. 6466
Sponsoring Org:
National Science Foundation
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