INIFTA   05425
INSTITUTO DE INVESTIGACIONES FISICO-QUIMICAS TEORICAS Y APLICADAS
Unidad Ejecutora - UE
artículos
Título:
Non-Hermitian Hamiltonians with unitary and antiunitary symmetries
Autor/es:
FRANCISCO M. FERNÁNDEZ; JAVIER GARCIA
Revista:
ANNALS OF PHYSICS (NEW YORK)
Editorial:
ACADEMIC PRESS INC ELSEVIER SCIENCE
Referencias:
Lugar: New York; Año: 2014 vol. 342 p. 195 - 204
ISSN:
0003-4916
Resumen:
Weanalyseseveralnon-HermitianHamiltonianswithantiunitary
symmetryfromthepointofviewoftheirpoint-groupsymmetry.
It enables us to predict the degeneracy of the energy levels
and to reduce the dimension of the matrices necessary for the
diagonalizationoftheHamiltonianinagivenbasisset.Wecanalso
classifythesolutionsaccordingtotheirreduciblerepresentations
of the point group and thus analyse their properties separately.
One of the main results of this paper is that some PT-symmetric
Hamiltonians with point-group symmetryC2v
exhibit complex
eigenvalues for all values of a potential parameter. In such cases
the PT phase transition takes place at the trivial Hermitian limit
which suggests that the phenomenon is not robust. Point-group
symmetryenablesustoexplainsuchanomalousbehaviourandto
chooseasuitableantiunitaryoperatorforthePTsymmetry.