Related papers: Anomalous mechanisms of the loss of observability in non-Hermitian quantum models

Anomalous mechanisms of the loss of observability in non-Hermitian quantum models

URL: http://arxiv.org/abs/2005.13069v1
Date: Tue, 26 May 2020 22:25:06 GMT
Title: Anomalous mechanisms of the loss of observability in non-Hermitian quantum models
Authors: Miloslav Znojil and Denis I. Borisov
Abstract summary: Quantum phase transitions in certain non-Hermitian systems controlled by non-tridiagonal Hamiltonian matrices are found anomalous. The phenomenon is interpreted as a confluence of several decoupled Kato's exceptional points of equal or different orders.
Score: 0.0
License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
Abstract: Quantum phase transitions in certain non-Hermitian systems controlled by non-tridiagonal Hamiltonian matrices are found anomalous. In contrast to the known models with tridiagonal-matrix structure in which the geometric multiplicity of the completely degenerate energy eigenvalue appears always equal to one, this multiplicity is found larger than one in the present models. The phenomenon is interpreted as a confluence of several decoupled Kato's exceptional points of equal or different orders.

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