Rydberg Atoms in a Ladder Geometry: Quench Dynamics and Floquet Engineering

Abstract: In recent days, Rydberg atom quantum simulator platforms have emerged as novel quantum simulators for physical systems ranging from condensed matter to particle physics. On a fundamental level, these platforms allow for a direct test of our understanding of the emergence of quantum statistical mechanics starting from the laws of quantum dynamics. In this paper, we investigate the fate of quantum dynamics in a model of Rydberg atoms arranged in a square ladder geometry, with a Rabi frequency $2\Omega$ and a detuning profile which is staggered along the longer direction with amplitude $\Delta$. As the staggering strength $\Delta$ is tuned from $\Delta/\Omega=0\rightarrow\infty$, the model exhibits a wide class of dynamical phenomena, ranging from (i) quantum many-body scars (QMBS) ($\Delta/\Omega \sim 0,1$), (ii) integrability induced slow dynamics and approximate Krylov fractures ($\Delta/\Omega \gg 1$) . Additionally, by leveraging the underlying chiral nature of the spectrum of this model Hamiltonian, it is possible to design Floquet protocols leading to dynamical signatures reminiscent of discrete time-crystalline order and exact Floquet flat bands. Finally, we study the robustness of these dynamical features against imperfections in the implementation of the Floquet protocols, long-range van der Waals interactions and inevitable influences from the environment in the form of pure dephasing and the finite lifetime of the Rydberg excited state.