Hermitian--to--quasi-Hermitian quantum phase transitions

Abstract

The phenomenon of quantum phase transition is considered in the special case in which the evolution laws remain unitary and in which the bound-state energies remain observable. The conventional Hermiticity of observables is lost at the interface, replaced by the so called quasi-Hermiticity. Several features of the passage of the system through the interface are discussed and illustrated by elementary illustrative $\mathcal{P}\mathcal{T}-$symmetric examples.

24 pp., 5 figures

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Cited by in corpus (4)

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• Passage through exceptional point: Case study
• Broken Hermiticity phase transition in Bose-Hubbard model
• Quantum phase transitions mediated by clustered non-Hermitian degeneracies