Home > Research > Publications & Outputs > Bulk and edge-state arcs in non-Hermitian coupl...

Associated organisational unit

Electronic data

  • paper

    Accepted author manuscript, 3 MB, PDF-document

    Available under license: CC BY-NC: Creative Commons Attribution-NonCommercial 4.0 International License

  • PhysRevA.98.033807

    Final published version, 1 MB, PDF-document

Links

Text available via DOI:

View graph of relations

Bulk and edge-state arcs in non-Hermitian coupled-resonator arrays

Research output: Contribution to journalJournal article

Published
Article number033807
<mark>Journal publication date</mark>7/09/2018
<mark>Journal</mark>Physical Review A
Issue number3
Volume98
Number of pages10
<mark>State</mark>Published
<mark>Original language</mark>English

Abstract

We describe the formation of bulk and edge arcs in the dispersion relation of two-dimensional coupledresonator arrays that are topologically trivial in the Hermitian limit. Each resonator provides two asymmetrically coupled internal modes, as realized in noncircular open geometries, which enables the system to exhibit non-Hermitian physics. Neighboring resonators are coupled chirally to induce non-Hermitian symmetries. The bulk dispersion displays Fermi arcs connecting spectral singularities known as exceptional points and can be tuned to display purely real and imaginary branches. At an interface between resonators of different shape, one-dimensional edge states form that spectrally align along complex arcs connecting different parts of the bulk bands. We also describe conditions under which the edge-state arcs are freestanding. These features can be controlled via anisotropy in the resonator couplings.