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arXiv · 0802.2457

Visualization of Branch Points in PT-Symmetric Waveguides

Shachar Klaiman·Nimrod Moiseyev·Uwe Gunther
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Abstract

The visualization of an exceptional point in a PT symmetric directional coupler(DC) is demonstrated. In such a system the exceptional point can be probed by varying only a single parameter. Using the Rayleigh-Schroedinger perturbation theory we prove that the spectrum of a PT symmetric Hamiltonian is real as long as the radius of convergence has not been reached. We also show how one can use a PT symmetric DC to measure the radius of convergence for non PT symmetric structures. For such systems the physical meaning of the rather mathematical term: radius of convergence, is exemplified.

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Shachar Klaiman, Nimrod Moiseyev, Uwe Gunther. 2008-02-18. Visualization of Branch Points in PT-Symmetric Waveguides. https://doi.org/10.1103/physrevlett.101.080402

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