Unitary unfoldings of a Bose-Hubbard exceptional point with and without particle number conservation
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F62690094%3A18470%2F20%3A50017331" target="_blank" >RIV/62690094:18470/20:50017331 - isvavai.cz</a>
Alternative codes found
RIV/61389005:_____/20:00534289
Result on the web
<a href="https://royalsocietypublishing.org/doi/10.1098/rspa.2020.0292" target="_blank" >https://royalsocietypublishing.org/doi/10.1098/rspa.2020.0292</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1098/rspa.2020.0292" target="_blank" >10.1098/rspa.2020.0292</a>
Alternative languages
Result language
angličtina
Original language name
Unitary unfoldings of a Bose-Hubbard exceptional point with and without particle number conservation
Original language description
The conventional non-Hermitian but PT-symmetric three-parametric Bose-Hubbard Hamiltonian H(gamma, v, c) represents a quantum system of N bosons, unitary only for parameters gamma, v and c in a domain D. Its boundary partial derivative D contains an exceptional point of order K (EPK; K=N+1) at c=0 and gamma=v, but even at the smallest non-vanishing parameter c not equal 0 the spectrum of H(v, v, c) ceases to be real, i.e. the system ceases to be observable. In this paper, the question is inverted: all of the stable, unitary and observable Bose-Hubbard quantum systems are sought which would lie close to the phenomenologically most interesting EPK-related dynamical regime. Two different families of such systems are found. Both of them are characterized by the perturbed Hamiltonians H(lambda)=H(v,v,0)+lambda V for which the unitarity and stability of the system is guaranteed. In the first family the number N of bosons is assumed conserved while in the second family such an assumption is relaxed. Attention is paid mainly to an anisotropy of the physical Hilbert space near the EPK extreme. We show that it is reflected by a specific, operationally realizable structure of perturbations lambda V which can be considered small.
Czech name
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Czech description
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Classification
Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
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OECD FORD branch
10303 - Particles and field physics
Result continuities
Project
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Continuities
I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace
Others
Publication year
2020
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences
ISSN
1364-5021
e-ISSN
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Volume of the periodical
476
Issue of the periodical within the volume
2242
Country of publishing house
GB - UNITED KINGDOM
Number of pages
19
Pages from-to
"Article Number: 20200292"
UT code for WoS article
000581913500001
EID of the result in the Scopus database
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