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arXiv · 0804.4578

A criterion for the reality of the spectrum of PT symmetric Schroedinger operators with complex-valued periodic potentials

E. Caliceti·S. Graffi
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Abstract

Consider in $L^2(\R)$ the \Sc operator family $H(g):=-d^2_x+V_g(x)$ depending on the real parameter $g$, where $V_g(x)$ is a complex-valued but $PT$ symmetric periodic potential. An explicit condition on $V$ is obtained which ensures that the spectrum of $H(g)$ is purely real and band shaped; furthermore, a further condition is obtained which ensures that the spectrum contains at least a pair of complex analytic arcs.

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E. Caliceti, S. Graffi. 2008-04-29. A criterion for the reality of the spectrum of PT symmetric Schroedinger operators with complex-valued periodic potentials. https://arxiv.org/abs/0804.4578

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