12 citations · 12 across the 2 of their papers we have counts for
8 papers
On Kippenhahn curves and higher-rank numerical ranges of some matrices
Natália Bebiano, Joáo da Providéncia, Ilya M. Spitkovsky
The higher rank numerical ranges of generic matrices are described in terms of the components of their Kippenhahn curves. Cases of tridiagonal (in particular, reciprocal) 2-periodi…
Kippenhahn curves of some tridiagonal matrices
Natália Bebiano, Joáo da Providéncia, Ilya M. Spitkovsky +1
Tridiagonal matrices with constant main diagonal and reciprocal pairs of off-diagonal entries are considered. Conditions for such matrices with sizes up to 6-by-6 to have elliptica…
A quantum system with a non-Hermitian Hamiltonian
Natália Bebiano, João da Providência, S. Nishiyama +1
The relevance in Physics of non-Hermitian operators with real eigenvalues is being widely recognized not only in quantum mechanics but also in other areas, such as quantum optics,…
Towards non-Hermitian quantum statistical thermodynamics
Natália Bebiano, João da Providência, João P. da Providência
Non-Hermitian Hamiltonians possessing a discrete real spectrum motivated a remarkable research activity in quantum physics and new insights have emerged. In this paper we formulate…
Fermionic model with a non-Hermitian Hamiltonian
Natália Bebiano, João da Providência, Seiya Nishiyama +1
This paper deals with the mathematical spectral analysis and physical interpretation of a fermionic system described by a non-Hermitian Hamiltonian possessing real eigenvalues. A s…
Non self-adjoint operators with real spectra and extensions of quantum mechanics
N. Bebiano, J. da Providência
In this article, we review the general quantum mechanical setting associated to a non self-adjoint Hamiltonian with real spectrum. Spectral properties of the Hamiltonian of a simpl…