## Research interests

-- Description of small open quantum systems on the basis of an exact theory with a non-hermitian Hamilton operator Examples: spectroscopic studies on light nuclei laser induced continuum structures in atoms transmission in quantum billiards -- Dynamics of small quantum systems In particular: resonance trapping in the overlapping regime relation to exceptional points in the complex energy plane study of the avoided crossing scenario of discrete and narrow resonance states phase rigidity of the scattering wave function bound states in the continuum width bifurcation at high level density -- Topology of branch points in the complex energy plane