Abstract
Weyl points—topological monopoles of quantized Berry flux—are predicted to spread to Weyl exceptional rings in the presence of non-Hermiticity. Here, we use a one-dimensional Aubry-Andre-Harper model to construct a Weyl semimetal in a three-dimensional parameter space comprising one reciprocal dimension and two synthetic dimensions. The inclusion of non-Hermiticity in the form of gain and loss produces a synthetic Weyl exceptional ring (SWER). The topology of the SWER is characterized by both its topological charge and non-Hermitian winding numbers. We experimentally observe the SWER and synthetic Fermi arc in a one-dimensional phononic crystal with the non-Hermiticity introduced by active acoustic components. Our findings pave the way for studying the high-dimensional non-Hermitian topological physics in acoustics.
Original language | English |
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Article number | 084301 |
Journal | Physical Review Letters |
Volume | 129 |
Issue number | 8 |
DOIs | |
Publication status | Published - 19 Aug 2022 |
Scopus Subject Areas
- Physics and Astronomy(all)