English

PT-symmetric scattering in flow duct acoustics

Classical Physics 2017-05-03 v1

Abstract

We show theoretically and experimentally that the propagation of an acoustic wave in an airflow duct going through a pair of diaphragms, with equivalent amount of mean-flow-induced effective gain and loss, displays all the features of a parity-time (PT) symmetric system. Using a scattering matrix formalism, we observe experimentally the properties which reflect the PT-symmetry of the scattering acoustical system: the existence of a spontaneous symmetry breaking with symmetry-broken pairs of scattering eigenstates showing amplification and reduction, and the existence of points with unidirectional invisibility.

Keywords

Cite

@article{arxiv.1701.07618,
  title  = {PT-symmetric scattering in flow duct acoustics},
  author = {Yves Aurégan and Vincent Pagneux},
  journal= {arXiv preprint arXiv:1701.07618},
  year   = {2017}
}

Comments

5 pages, 5 figures

R2 v1 2026-06-22T18:00:59.819Z