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Comment on ''Exceptional points and double poles of the S matrix''

C. Dembowski·B. Dietz·H. -D. Graef·H. L. Harney·A. Heine·W. D. Heiss·A. Richter
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Abstract

In a recent paper [Phys. Rev. E 67, 026204 (2003)], Rotter calculates the geometric phases that are picked up by the eigenvectors of a two-state quantum system when an exceptional point is encircled. In addition to the geometric phases observed by Dembowski et al. in a microwave cavity experiment [Phys. Rev. Lett. 86, 787 (2001)], she finds a phase factor of i. We show that Rotters results are inconsistent.

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C. Dembowski, B. Dietz, H. -D. Graef, H. L. Harney, A. Heine, W. D. Heiss, A. Richter. 2003-09-25. Comment on ''Exceptional points and double poles of the S matrix''. https://arxiv.org/abs/nlin/0309066

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