Abstract
The realization of higher-order exceptional points (HOEPs) can lead to orders of magnitude enhancement in light-matter interactions beyond the current fundamental limits. Unfortunately, implementing HOEPs in the existing schemes is a rather difficult task, due to the complexity and sensitivity to fabrication imperfections. Here we introduce a hierarchical approach for engineering photonic structures having HOEPs that are easier to build and more resilient to experimental uncertainties. We demonstrate our technique by an example that involves parity-time symmetric optical microring resonators with chiral coupling among the internal optical modes of each resonator. Interestingly, we find that the uniform coupling profile is not required to achieve HOEPs in this system-a feature that implies the emergence of HOEPs from disorder and provides resilience against some fabrication errors. Our results are confirmed by using full-wave simulations based on Maxwell's equation in realistic optical material systems.
Highlights
Introduction.—The notion of non-Hermitian photonics [1,2,3,4], together with its central concept of exceptional points (EPs) [5], has attracted considerable attention in the past few years
In this Letter, we introduce a general approach for constructing tight-binding networks supporting higherorder exceptional points (HOEPs) out of arrangements that support only lower-order EPs
We apply our scheme for constructing photonic networks with HOEPs based on judicious engineering of the gain-loss profile and coupling coefficients in both real and synthetic dimensions
Summary
Introduction.—The notion of non-Hermitian photonics [1,2,3,4], together with its central concept of exceptional points (EPs) [5], has attracted considerable attention in the past few years. In this Letter, we introduce a general approach for constructing tight-binding networks supporting higherorder exceptional points (HOEPs) out of arrangements that support only lower-order EPs. As an example, we apply our scheme for constructing photonic networks with HOEPs based on judicious engineering of the gain-loss profile and coupling coefficients in both real and synthetic dimensions.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
