PT-symmetric waveguide system with evidence of a third-order exceptional point
CITATION: Schnabel, J., et al. 2017. PT-symmetric waveguide system with evidence of a third-order exceptional point. Physical Review A, 95(5):053868, doi:10.1103/PhysRevA.95.053868.
The original publication is available at http://journals.aps.org/pra
An experimental setup of three coupled PT -symmetric waveguides showing the characteristics of a third-order exceptional point (EP3) has been investigated by Heiss and Wunner in an idealized model of three δ-function waveguides [W. D. Heiss and G. Wunner, J. Phys. A 49, 495303 (2016)]. Here we extend these investigations to realistic, extended waveguide systems. We place major focus on the strong parameter sensitivity rendering the discovery of an EP3 a challenging task. We also investigate the vicinity of the EP3 for further branch points of either cubic- or square-root-type behavior.