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Non-Hermitian degeneracy of two unbound states

E. Hernandez·A. Jauregui·A. Mondragon
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Abstract

We solved numerically the implicit, trascendental equation that defines the eigenenergy surface of a degenerating isolated doublet of unbound states in the simple but illustrative case of the scattering of a beam of particles by a double barrier potential. Unfolding the degeneracy point with the help of a contact equivalent approximant, crossings and anticrossings of energies and widths, as well as the changes of identity of the poles of the S-matrix are explained in terms of sections of the eigenenergy surfaces.

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E. Hernandez, A. Jauregui, A. Mondragon. 2006-06-29. Non-Hermitian degeneracy of two unbound states. https://doi.org/10.1088/0305-4470/39/32/s11

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