Dynamical quantum phase transition in 1D quantum link model
Dynamics of the out-of-equilibrium correlated quantum many-body systems is a new region to explore emergent quantum phases of matter. The concept of dynamical quantum phase transitions(DQPTs) provides one framework for understanding the dynamics of correlated quantum matters. In this work, we study particle-antiparticle production in the quantum quench dynamics after a strong coupling of the bare particles to dynamical gauge field in a quantum link model. Particle-antiparticle production in the presence of a static classical electric field, known as the Schwinger mechanism, represents a central physical phenomenon in gauge theories. How the particle production is affected in the quantum limit, where the backaction onto the electric field becomes essential, remains a major challenge. We find that for a strong coupling the system experiences DQPTs where the vacuum persistence probability (Loschmidt echo) develops non-analytic behavior at critical times. As opposed to the Schwinger mechanism, where matter fields are suddenly coupled to a classical electric field, we observe that the dynamics of the vacuum persistence probability and therefore the DQPTs cannot be understood using the classical picture of particle production. Instead, a quantum dynamical pattern emerges from the strongly coupled matter fields and dynamical gauge fields.