skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Scaling behavior and phase diagram of a PT-symmetric non-Hermitian Bose-Hubbard system

Journal Article · · Annals of Physics (New York)

We study scaling behavior and phase diagram of a PT-symmetric non-Hermitian Bose-Hubbard model. In the free interaction case, using both analytical and numerical approaches, the metric operator for many-particle is constructed. The derived properties of the metric operator, similarity matrix and equivalent Hamiltonian reflect the fact that all the matrix elements change dramatically with diverging derivatives near the exceptional point. In the nonzero interaction case, it is found that even small on-site interaction can break the PT symmetry drastically. It is demonstrated that the scaling law can be established for the exceptional point in both small and large interaction limit. Based on perturbation and numerical methods, we also find that the phase diagram shows rich structure: there exist multiple regions of unbroken PT symmetry. - Highlights: Black-Right-Pointing-Pointer Generalization is done to many-particle sector of PT-symmetric non-Hermitian system. Black-Right-Pointing-Pointer The metric operator, similarity matrix and equivalent Hamiltonian possess diverging derivatives near the exceptional point. Black-Right-Pointing-Pointer The scaling law is established for the exceptional point of a PT-symmetric non-Hermitian Bose-Hubbard model. Black-Right-Pointing-Pointer The phase diagram shows that multiple regions of unbroken PT symmetry exist. Black-Right-Pointing-Pointer It is shown that even small on-site interaction can break the PT symmetry drastically.

OSTI ID:
22157082
Journal Information:
Annals of Physics (New York), Vol. 330; Other Information: Copyright (c) 2012 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-4916
Country of Publication:
United States
Language:
English