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Related papers: Critical parameters for non-hermitian Hamiltonians

200 papers

A new proof is given for why the non-Hermitian, PT-Invariant cubic oscillator with imaginary coupling has real eigenvalues. The proof consists of two steps. In the first step, it is shown that for many PT-Invariant Hamiltonians, one can…

Mathematical Physics · Physics 2009-10-28 Scott Chapman

Non-hermiticity presents a vast newly opened territory that harbors new physics and applications such as lasing and sensing. However, only non-Hermitian systems with real eigenenergies are stable, and great efforts have been devoted in…

Other Condensed Matter · Physics 2022-10-25 Russell Yang , Jun Wei Tan , Tommy Tai , Jin Ming Koh , Linhu Li , Stefano Longhi , Ching Hua Lee

Despite acute interest in the dynamics of non-Hermitian systems, there is a lack of consensus in the mathematical formulation of non-Hermitian quantum mechanics in the community. Different methodologies are used in the literature to study…

Quantum Physics · Physics 2025-03-31 Karin Sim , Nicolò Defenu , Paolo Molignini , R. Chitra

A condition to have a real spectrum for a non-Hermitian Hamiltonian is given. As special cases, it is shown that the condition is reduced to Hermiticity and PT symmetric conditions.

Quantum Physics · Physics 2015-02-26 C. Yuce

We introduce and develop a novel approach to extend the ordinary two-flavor neutrino oscillation formalism in matter using a non-Hermitian PT symmetric effective Hamiltonian. The condition of PT symmetry is weaker and less mathematical than…

High Energy Physics - Phenomenology · Physics 2016-04-14 Tommy Ohlsson

We provide a reviewlike introduction into the quantum mechanical formalism related to non-Hermitian Hamiltonian systems with real eigenvalues. Starting with the time-independent framework we explain how to determine an appropriate domain of…

Quantum Physics · Physics 2015-06-26 Carla Figueira de Morisson Faria , Andreas Fring

We develop relativistic non-Hermitian quantum theory and its application to neutrino physics in a strong magnetic field. It is well known, that one of the fundamental postulates of quantum theory is the requirement of Hermiticity of…

High Energy Physics - Phenomenology · Physics 2016-03-25 V. N. Rodionov

In recent decades, an important shift has taken place with the growing role of non-Hermitian quantum mechanics. What makes this framework remarkable is that the eigenvalues of the Hamiltonians involved can still be real, just as in the…

Quantum Physics · Physics 2025-09-30 Maamache Mustapha

We generalize the concept of population for non-Hermitian systems in different ways and identify the one best suited to characterize adiabaticity. An approximate adiabaticity criterion consistent with this choice is also worked out.…

Quantum Physics · Physics 2015-06-18 S. Ibáñez , J. G. Muga

Hamiltonian Mechanics works for conserved systems and Quantum Mechanics is given in Hamiltonian language. It is considered that complexifying the quantum Hamiltonian, a balanced loss and gain model can be created. The usual mathematics of…

General Physics · Physics 2015-12-03 Chetan Waghela

We consider a class of (possibly nondiagonalizable) pseudo-Hermitian operators with discrete spectrum, showing that in no case (unless they are diagonalizable and have a real spectrum) they are Hermitian with respect to a semidefinite inner…

Quantum Physics · Physics 2015-06-26 G. Scolarici , L. Solombrino

We demonstrate that a non self-adjoint Hamiltonian of harmonic oscillator type defined on a two-dimensional noncommutative space can be diagonalized exactly by making use of pseudo-bosonic operators. The model admits an antilinear symmetry…

Quantum Physics · Physics 2013-11-01 Fabio Bagarello , Andreas Fring

We formulate a systematic algorithm for constructing a whole class of Hermitian position-dependent-mass Hamiltonians which, to lowest order of perturbation theory, allow a description in terms of PT-symmetric Hamiltonians. The method is…

Quantum Physics · Physics 2009-11-11 B. Bagchi , C. Quesne , R. Roychoudhury

In this talk we go over several new developments regarding the techniques for a large class of non-hermitian matrix models with unitary randomness (complex random numbers). In particular, we discuss: (a) - A diagrammatic approach based on a…

High Energy Physics - Phenomenology · Physics 2008-02-03 Romuald A. Janik , Maciej A. Nowak , Gabor Papp , Ismail Zahed

A generic PT-symmetric Hamiltonian is assumed tridiagonalized and truncated to N dimensions, and its up-down symmetrized special cases with J=[N/2] real couplings are considered. In the strongly non-Hermitian regime the secular equation…

Mathematical Physics · Physics 2008-02-10 Miloslav Znojil

The non-Hermitian formalism is used at present in many papers for the description of open quantum systems. A special language developed in this field of physics which makes it difficult for many physicists to follow and to understand the…

Quantum Physics · Physics 2018-12-11 Hichem Eleuch , Ingrid Rotter

One-dimensional scattering mediated by non-Hermitian Hamiltonians is studied. A schematic set of models is used which simulate two point interactions at a variable strength and distance. The feasibility of the exact construction of the…

Quantum Physics · Physics 2008-06-26 Miloslav Znojil

A family of non-Hermitian but ${\cal PT}-$symmetric $2J$ by $2J$ toy-model tridiagonal-matrix Hamiltonians $H^{(2J)}=H^{(2J)}(t)$ with $J=K+M=1,2,\ldots$ and $t<J^2$ is studied, for which a real but non-Hermitian $2K$ by $2K$…

Mathematical Physics · Physics 2022-12-21 Miloslav Znojil

We present an evaluation of some recent attempts at understanding the role of pseudo-Hermitian and PT-symmetric Hamiltonians in modeling unitary quantum systems and elaborate on a particular physical phenomenon whose discovery originated in…

Quantum Physics · Physics 2015-05-14 Ali Mostafazadeh

We construct effective Hamiltonians which despite their apparently nonrelativistic form incorporate relativistic effects by involving parameters which depend on the relevant momentum. For some potentials the corresponding energy eigenvalues…

High Energy Physics - Phenomenology · Physics 2016-09-01 Wolfgang LUCHA , Franz F. SCHÖBERL