Critical dynamics of coherence in extended transverse field Ising model

In a many-body quantum system, the interplay of various energies and entropies leads to different phases. The system undergoes a phase transition in the case that certain feature becomes dominant over all the others by varying either adjustable interaction constants or applied external fields in the Hamiltonian. In this work, we investigate the quantum phase transition from the perspective of coherence through a significant model. It is shown that when an extra two-level system is injected into the transverse field Ising model, its coherence will suffer an explicit sudden change in dynamics around the phase transition point of the surrounding model. With such dynamic sensitivity, coherence can be exploited to characterize quantum phase transitions and reveal the location of critical point.