title: A note on the topological insulator phase in non-Hermitian quantum systems.
abstract: Examples of non-Hermitian quantum systems admitting a topological insulator phase are presented in one, two and three space dimensions. All of these non-Hermitian Hamiltonians have entirely real bulk eigenvalues and unitarity is maintained with the introduction of appropriate inner products in the corresponding Hilbert spaces. The topological invariant characterizing a particular phase is shown to be identical for a non-Hermitian Hamiltonian and its Hermitian counterpart, to which it is related through a non-unitary similarity transformation. A classification scheme for topological insulator phases in pseudo-Hermitian quantum systems is suggested.
authors.affiliation: Department of Physics, Siksha-Bhavana, Visva-Bharati University, Santiniketan, PIN 731 235, India. pijushkanti.ghosh@visva-bharati.ac.in
authors.forename: Pijush K
authors.initials: PK
authors.lastname: Ghosh
mesh_terms: D000465:Algorithms; D003198:Computer Simulation; D015233:Models, Statistical; D017711:Nonlinear Dynamics; D044367:Phase Transition; D011789:Quantum Theory; D014159:Transducers