Late-time critical behavior of local string-like observables under quantum quenches

Abstract

In recent times it has been observed that signatures of equilibrium quantum criticality surprisingly show up in many-body systems which are manifestly far from equilibrium. We explore such scenarios in interacting spin systems subject to a quench and develop a robust method to systematically probe ground state critical physics through nonequilibrium post-quench dynamics. Analyzing late-time behavior of finite string-like observables, we find emerging sharp signatures of equilibrium criticality. Specifically, these observables accurately detect equilibrium critical points and universal scaling exponents after long times following a quench. This happens despite the fact that the analyzed systems are strongly chaotic/ergodic and is interestingly due to a strong memory of the initial conditions retained by these observables after quench. We find that our results can also be used to explain critical signatures in post-quench domain formation, seen in a recent experiment with trapped ion quantum simulators.

25 pages, 22 captioned figures

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Cited by in corpus (5)

• Dynamical quantum phase transition and thermal equilibrium in the lattice Thirring model
• Signature of quantum phase transition manifested in quantum fidelity at finite temperature
• Eigenstate Thermalization in 1+1-Dimensional SU(2) Lattice Gauge Theory Coupled with Dynamical Fermions
• Signatures of quantum phases in a dissipative system
• Distinguishing dynamical quantum criticality through local fidelity distances