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Title: Non-Hermitian and topological photonics: optics at an exceptional point
Abstract In the past few years, concepts from non-Hermitian (NH) physics, originally developed within the context of quantum field theories, have been successfully deployed over a wide range of physical settings where wave dynamics are known to play a key role. In optics, a special class of NH Hamiltonians – which respects parity-time symmetry – has been intensely pursued along several fronts. What makes this family of systems so intriguing is the prospect of phase transitions and NH singularities that can in turn lead to a plethora of counterintuitive phenomena. Quite recently, these ideas have permeated several other fields of science and technology in a quest to achieve new behaviors and functionalities in nonconservative environments that would have otherwise been impossible in standard Hermitian arrangements. Here, we provide an overview of recent advancements in these emerging fields, with emphasis on photonic NH platforms, exceptional point dynamics, and the very promising interplay between non-Hermiticity and topological physics.  more » « less
Award ID(s):
1805200 2011171 2000538 1757025 1454531
NSF-PAR ID:
10298091
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Nanophotonics
Volume:
10
Issue:
1
ISSN:
2192-8606
Page Range / eLocation ID:
403 to 423
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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