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  • Universal route for the emergence of exceptional points in PT-symmetric metamaterials with unfolding spectral symmetries
Title: Universal route for the emergence of exceptional points in PT-symmetric metamaterials with unfolding spectral symmetries
Abstract We introduce a class of parity-time symmetric elastodynamic metamaterials (Ed-MetaMater) whose Hermitian counterpart exhibits unfolding (fractal) spectral symmetries. Our study reveals a scale-free formation of exceptional points in those Ed-MetaMaters whose density is dictated by the fractal dimension of their Hermitian spectra. We demonstrate this scale-free EP-formation in a quasi-periodic Aubry-Harper Ed-MetaMater, a geometric H-tree-fractal Ed-MetaMater, and an aperiodic Fibonacci Ed-MetaMater—each having a specific fractal spectrum—using finite element models and establish a universal route for EP-formation via a coupled mode theory model with controllable fractal spectrum. This universality may enable the rational design of novel Ed-MetaMater for hypersensitive sensing and elastic wave control.  more » « less
Award ID(s):
1925543 1925530
PAR ID:
10326686
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
New Journal of Physics
Volume:
23
Issue:
6
ISSN:
1367-2630
Page Range / eLocation ID:
063079
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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