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Title: Sensing Via Exceptional Points in Space and Time Periodic Systems and in PT-Symmetric Systems
We review and explore sensor applications based on electromagnetic systems operating near an exceptional point of degeneracy (EPD). The EPD is defined as the point at which the system eigenmodes coalesce in both their eigenvalues and eigenvectors varying a system parameter. Sensors based on EPDs show sensitivity proportional to δ 1/m , where δ is a perturbation of a system parameter and m is the order of the EPD. EPDs manifest in PT-symmetric systems or periodic systems that can be periodic in either time or space. We review all the methods to obtain EPD based sensors, and we focus on two classes of ultra-sensitive EPD systems: i) periodic linear time-varying single oscillators, and ii) optical gyroscopes based on a modified coupled resonators optical waveguide (CROW) exhibiting 4th order EPD.  more » « less
Award ID(s):
1711975
PAR ID:
10421540
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Published in: 2020 Fourteenth International Congress on Artificial Materials for Novel Wave Phenomena (Metamaterials)
Page Range / eLocation ID:
New York, NY, Sept. 2021
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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