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arXiv · 1703.05091

$\mathcal{PT}$-symmetric wave guide system with evidence of a third-order exceptional point

Jan Schnabel·Holger Cartarius·Jörg Main·Günter Wunner·Walter Dieter Heiss
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Abstract

An experimental setup of three coupled $\mathcal{PT}$-symmetric wave guides showing the characteristics of a third-order exceptional point (EP3) has been investigated in an idealized model of three delta-functions wave guides in W.~D. Heiss and G.~Wunner, J. Phys. A 49, 495303 (2016). Here we extend these investigations to realistic, extended wave guide 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.

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Jan Schnabel, Holger Cartarius, Jörg Main, Günter Wunner, Walter Dieter Heiss. 2017-05-11. $\mathcal{PT}$-symmetric wave guide system with evidence of a third-order exceptional point. https://doi.org/10.1103/physreva.95.053868

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