Resonance Trapping and Dynamical Phase Transitions

In the non-Hermitian quantum physics, resonance trapping occurs due to width bifurcation in the regime of overlapping resonances. It causes dynamical phase transitions in many-level quantum systems. In the present contribution, three different examples, observed experimentally, are considered. In any case, resonance trapping breaks the symmetry characteristic of the system at low level density due to the alignment of a few states with the scattering states of the environment.