Scattering cross section resonance originating from a spectral singularity

Autor: Samsonov, Boris F.
Rok vydání: 2010
Předmět:
Zdroj: J.Phys.A44:392001,2011
Druh dokumentu: Working Paper
DOI: 10.1088/1751-8113/44/39/392001
Popis: Using techniques of supersymmetric quantum mechanics, scattering properties of Hermitian Hamiltonians, which are related to non-Hermitian ones by similarity transformations, are studied. We have found that the scattering matrix of the Hermitian Hamiltonian coincides with the phase factor of the non-unitary scattering matrix of the non-Hermitian Hamiltonian. The possible presence of a spectral singularity in a non-Hermitian Hamiltonian translates into a pronounced resonance in the scattering cross section of its Hermitian counterpart. This opens a way for detecting spectral singularities in scattering experiments; although a singular point is inaccessible for the Hermitian Hamiltonian, the Hamiltonian "feels" the presence of the singularity if it is "close enough". We also show that cross sections of the non-Hermitian Hamiltonian do not exhibit any resonance behavior and explain the resonance behavior of the Hermitian Hamiltonian cross section by the fact that corresponding scattering matrix, up to a background scattering matrix, is a square root of the Breit-Wigner scattering matrix.
Comment: Minor modifications are made following recommendations of Referee
Databáze: arXiv