Critical phenomena associated with self-orthogonality in non-Hermitian quantum mechanics

E. NAREVIVIUS; PABLO SERRA; NIMROD MOISEYEV

EUROPHYSICS LETTERS

EPL ASSOCIATION

Lugar: Bologna; Año: 2003 vol. 62 p. 789 - 794

0295-5075

The delocalization phenomenon was discovered by Hatano et al. and Miller et al. for a class of non-Hermitian quantum-mechanical problems. We show that the delocalization is only one example of many possible critical phenomena which are associated with the self-orthogonality of an eigenstate of the non-Hermitian Hamiltonian. It is shown that in this class of problems the self-orthogonality occurs at the series of branch points in the complex energy plane that serve as gates for the "particle" to hop from one Bloch energy band to another one.