Effects of excited state quantum phase transitions on system dynamics

Understand

This work is concerned with the excited state quantum phase transitions (ESQPTs) defined in Ann.Phys.

• 323, 1106 (2008).
• In many-body models that exhibit such transitions, the ground state quantum phase transition (QPT) occurs in parallel with a singularity in the energy spectrum that propagates to higher energies as the control parameter increases beyond the QPT critical point.
• The analysis of the spectrum has been a main tool for the detection of these ESQPTs.