Regular Article

Chiral behaviour of the wave functions for three wave guides in the vicinity of an exceptional point of third order

¹ Department of Physics, University of Stellenbosch, 7602 Matieland, South Africa
² National Institute for Theoretical Physics (NITheP), Western Cape, South Africa
³ Institut für Theoretische Physik, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart, Germany

^a e-mail: wunner@itp1.uni-stuttgart.de

Received: 17 July 2017
Published online: 5 December 2017

Abstract

A matrix model that has been used to describe essential features of a parity-time symmetric set-up of three coupled wave guides is investigated. The emphasis of the study lies on the occurrence of an exceptional point of third order. It is demonstrated that the eigenfunctions in close vicinity of the exceptional point have a distinctive chiral behaviour. Using data describing realistic situations it is argued that such chiral behaviour can be tested experimentally.