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Fragile PT-symmetry in a solvable model

Miloslav Znojil
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Abstract

One of the simplest pseudo-Hermitian models with real spectrum (viz., square-well on a real interval I of coordinates) is re-examined. A PT-symmetric complex deformation C of I is introduced and shown tractable via an innovated approach to matching conditions. The result is surprising: an arbitrarily small deformation I -> C implies a sudden collapse (i.e., the spontaneous PT-symmetry breaking) of virtually all the spectrum (i.e., up to its low-energy part).

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Miloslav Znojil. 2004-03-17. Fragile PT-symmetry in a solvable model. https://doi.org/10.1063/1.1803928

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