Fano-Feshbach resonances in two-channel scattering around exceptional points

Regular Article

DOI: 10.1140/epjd/e2014-50379-8

Cite this article as:
Heiss, W.D. & Wunner, G. Eur. Phys. J. D (2014) 68: 284. doi:10.1140/epjd/e2014-50379-8


It is well-known that in open quantum systems resonances can coalesce at an exceptional point, where both the energies and the wave functions coincide. In contrast to the usual behaviour of the scattering amplitude at one resonance, the coalescence of two resonances invokes a pole of second order in the Green’s function, in addition to the usual first order pole. We show that the interference due to the two pole terms of different order gives rise to patterns in the scattering cross section which closely resemble Fano-Feshbach resonances. We demonstrate this by extending previous work on the analogy of Fano-Feshbach resonances to classical resonances in a system of two driven coupled damped harmonic oscillators.


Atomic and Molecular Collisions 

Copyright information

© EDP Sciences, SIF, Springer-Verlag Berlin Heidelberg 2014

Authors and Affiliations

  1. 1.Department of PhysicsUniversity of StellenboschMatielandSouth Africa
  2. 2.National Institute for Theoretical Physics (NITheP)Western CapeSouth Africa
  3. 3.Institut für Theoretische PhysikUniversität StuttgartStuttgartGermany

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