arXiv:quant-ph/0206112
Point Interactions: PT-Hermiticity and Reality of the Spectrum
Sergio A Albeverio, S.-M. Fei, Pavel Kurasov
Abstract
General point interactions for the second derivative operator in one dimension are studied. In particular, ${\mathcal P \mathcal T}$-self-adjoint point interactions with the support at the origin and at points $\pm l$ are considered. The spectrum of such non-Hermitian operators is investigated and conditions when the spectrum is pure real are presented. The results are compared with those for standard self-adjoint point interactions.