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Title: Engineering interaction dynamics in active resonant photonic structures
The collective response of a system is profoundly shaped by the interaction dynamics between its constituent elements. In physics, tailoring these interactions can enable the observation of unusual phenomena that are otherwise inaccessible in standard settings, ranging from the possibility of a Kramer’s degeneracy even in the absence of spin to the breakdown of the bulk-boundary correspondence. Here, we show how tailored asymmetric coupling terms can be realized in photonic integrated platforms by exploiting non-Hermitian concepts. In this regard, we introduce a generalized photonic molecule composed of a pair of microring resonators with internal S-bends connected via two directional couplers and a link waveguide. By judiciously designing the parameters of this system, namely, the length of the links and the power division ratio of the directional couplers, we experimentally show the emergence of Hermitian and non-Hermitian-type exchange interactions. The ramifications of such coupling dynamics are then studied in 1D chain and ring-type active lattices. Our findings establish the proposed structure as a promising building block for the realization of a variety of phenomena, especially those associated with phase locking in laser arrays and non-Hermitian topological lattices.  more » « less
Award ID(s):
1805200 2011171 2000538
PAR ID:
10594456
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
American Institute of Physics
Date Published:
Journal Name:
APL Photonics
Volume:
6
Issue:
5
ISSN:
2378-0967
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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