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Non-Hermitian Hamiltonians with unitary and antiunitary symmetries
(Academic Press Inc Elsevier Science, 2014-03)
We analyse several non-Hermitian Hamiltonians with antiunitary symmetry from the point of view of their point-group symmetry. It enables us to predict the degeneracy of the energy levels and to reduce the dimension of the ...
Non-Hermitian oscillators with Td symmetry
(Academic Press Inc Elsevier Science, 2015-02)
We analyse some PT-symmetric oscillators with Td symmetry that depend on a potential parameter g. We calculate the eigenvalues and eigenfunctions for each irreducible representation and for a range of values of g. Pairs ...
Is space-time symmetry a suitable generalization of parity-time symmetry?
(Elsevier, 2014-08-08)
We discuss space-time symmetric Hamiltonian operators of the form H = H0 + igH ′ , where H0 is Hermitian and g real. H0 is invariant under the unitary operations of a point group G while H ′ is invariant under transformation ...
On the real matrix representation of pt-symmetric operators
(Czech Technical University, 2014-05)
We discuss the construction of real matrix representations of PT-symmetric operators. We show the limitation of a general recipe presented some time ago for non-Hermitian Hamiltonians with antiunitary symmetry and propose ...
Comment on "spontaneous breaking of permutation symmetry in pseudo-Hermitian quantum mechanics"
(American Physical Society, 2017-10)
Li and Miao [Phys. Rev. A 85, 042110 (2012)PLRAAN1050-294710.1103/PhysRevA.85.042110] proposed a non-Hermitian Hamiltonian that is neither Hermitian nor PT symmetric but exhibits real eigenvalues for some values of the ...
Three PT-symmetric Hamiltonians with completely different spectra
(Academic Press Inc Elsevier Science, 2015-12)
We discuss three Hamiltonians, each with a central-field part H0 and a PT-symmetric perturbation igz. When H0 is the isotropic Harmonic oscillator the spectrum is real for all g because H is isospectral to H0+g2/2. When ...
Enhanced energy harvesting near exceptional points in systems with (pseudo-) PT-symmetry
(Nature, 2021-04)
Exceptional point degeneracies, occurring in non-Hermitian systems, have challenged many well established concepts and led to the development of remarkable technologies. Here, we propose a family of autonomous motors whose ...
Parity-time symmetry broken by point-group symmetry
(American Institute of Physics, 2014-06)
We discuss a parity-time (PT) symmetric Hamiltonian with complex eigenvalues. It is based on the dimensionless Schrödinger equation for a particle in a square box with the PT-symmetric potential V(x, y) = iaxy. Perturbation ...