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arXiv · 1401.4043

Causality and phase transitions in PT-symmetrical optical systems

A. A. Zyablovsky·A. P. Vinogradov·A. V. Dorofeenko·A. A. Pukhov·A. A. Lisyansky
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Abstract

We discuss phase transitions in PT-symmetric optical systems. We show that due to frequency dispersion of the dielectric permittivity, an optical system can have PT-symmetry at isolated frequency points only. An assumption of the existence of a PT-symmetric system in a continuous frequency interval violates the causality principle. Therefore, the ideal symmetry-breaking transition cannot be observed by simply varying the frequency.

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A. A. Zyablovsky, A. P. Vinogradov, A. V. Dorofeenko, A. A. Pukhov, A. A. Lisyansky. 2014-01-16. Causality and phase transitions in PT-symmetrical optical systems. https://doi.org/10.1103/physreva.89.033808

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