Quantum information scrambling and entanglement generation in a Rydberg-dressed atom driven by tunable long-range interactions and quantum fluctuations

Arrays of Rydberg-dressed neutral atoms represent a preeminent quantum simulation platform, affording unparalleled in-situ control over many-body Hamiltonians. We investigate information scrambling in this system, governed by a physically derived and tunable soft-shoulder potential. To gain insight beyond a single measure of chaos, we leverage this tunability to demonstrate that scrambling is not a monolithic process. We dissect the information dynamics by computing a suite of out-of-time-order correlators, which allows us to probe distinct and coexisting information channels. Our central finding distinguishes a conventional chaotic channel from a rapid, wave-like channel for quantum coherence and a markedly suppressed channel for classical-like magnetization. We demonstrate systematic control over the landscape of quantum chaos by tuning the interaction range via laser detuning, which dramatically accelerates information propagation. Furthermore, by tuning the strength of quantum fluctuations with the transverse field, we identify an optimal chaotic sweet spot of maximal scrambling. This multifaceted picture is substantiated by a fundamental analysis of the system’s entangling power. Utilizing realistic parameters for 87Rb, our results provide a concrete recipe and quantitative predictions for upcoming experiments aiming to explore and control many-body chaos in atomic quantum simulators.