Abstract The anisotropic Dicke model offers a platform for exploring plentiful quantum many-body phenomena. Here, we propose a Floquet-engineered scheme to realize such a system with strong dipole-dipole interactions using Rydberg atom arrays in an optical cavity. By periodically modulating the microwave fields, the anisotropic parameter can be precisely controlled and tuned between zero and one, enabling the system to transition smoothly from being purely dominated by rotating wave terms to being exclusively governed by counter rotating wave excitations. Leveraging this tunability, we demonstrate enhanced adiabatic state preparation of superradiant and superradiant solid phases, where symmetry-protected energy gaps suppress undesired level crossings. Our approach, combining Rydberg interactions and cavity-mediated long-range correlations, establishes a versatile framework for quantum simulation of light-matter interactions and exploration of exotic many-body phases.
Abstract The anisotropic Dicke model offers a platform for exploring plentiful quantum many-body phenomena. Here, we propose a Floquet-engineered scheme to realize such a system with strong dipole-dipole interactions using Rydberg atom arrays in an optical cavity. By periodically modulating the microwave fields, the anisotropic parameter can be precisely controlled and tuned between zero and one, enabling the system to transition smoothly from being purely dominated by rotating wave terms to being exclusively governed by counter rotating wave excitations. Leveraging this tunability, we demonstrate enhanced adiabatic state preparation of superradiant and superradiant solid phases, where symmetry-protected energy gaps suppress undesired level crossings. Our approach, combining Rydberg interactions and cavity-mediated long-range correlations, establishes a versatile framework for quantum simulation of light-matter interactions and exploration of exotic many-body phases.
We study the properties of a generalized Dicke-Ising model realized with an array of Rydberg atoms, driven by microwave electric fields and coupled to an optical cavity. As this platform allows for a precisely tunable anisotropy parameter, the model exhibits a rich landscape of phase transitions and critical phenomena, induced by the interplay of rotating-wave, counter-rotating-wave, and Ising interactions. We develop an improved quantum Monte Carlo algorithm based on the stochastic series expansion that explicitly tracks the Fock state of the quantum cavity. In the superradiant (SR) phase, this allows us to determine, through data collapse, the scaling laws of the photon number. We also demonstrate the vanishing of parity symmetry in finite-size simulations and show that the Rydberg blockade leads to a significant suppression of cavity occupation. Notably, stronger quantum fluctuations induced by the counter-rotating wave terms slightly favor the superradiant solid (SRS) phase over the Solid-1/2 state. Finally, we confirm that the SR phase transition and the transition from the Solid-1/2 to the SRS are second-order. In contrast, the transitions from the Solid-1/2 or SRS to the SR phase are both first-order for any value of the normalized anisotropy parameter.
Arrays of Rydberg atoms interacting via dipole-dipole interactions offer a powerful platform for probing quantum many-body physics. However, these intrinsic interactions also determine and constrain the models-and parameter regimes thereof-for quantum simulation. Here, we propose a systematic framework to engineer arbitrary desired long-range interactions in Rydberg-atom lattices, enabling the realization of fully tunable J_{1}-J_{2}-J_{3} Heisenberg models. Using site-resolved periodic modulation of Rydberg states, we develop an experimentally feasible protocol to precisely control the interaction ratios J_{2}/J_{1} and J_{3}/J_{1} in a kagome lattice. This control can increase the effective range of interactions and drive transitions between competing spin-ordered and spin-liquid phases. To generalize this approach beyond the kagome lattice, we reformulate the design of modulation patterns through a graph-theoretic approach, demonstrating the universality of our method across all 11 planar Archimedean lattices. Our strategy overcomes the inherent constraints of power-law-decaying dipolar interactions, providing a versatile toolbox for exploring frustrated magnetism, emergent topological phases, and quantum correlations in systems with long-range interactions.
Scalable quantum computers and quantum networks require the combination of quantum processing nodes with efficient light-matter interfaces to distribute quantum information in local or long-distance quantum networks. Neutral-atom arrays have both been coupled to Rydberg states to enable high-fidelity quantum gates in universal processing architectures, and to optical cavities to realize interfaces to photons. However, combining these two capabilities and coupling atom arrays to highly excited Rydberg states in the mode of an optical cavity has been an outstanding challenge. Here we present a novel cavity-coupled Rydberg array that achieves this long-standing goal. We prepare, detect, and control individual atoms in a scalable optical tweezer array, couple them strongly to the optical mode of a high-finesse optical cavity and excite them in a controlled way to Rydberg states. We show that high-cooperativity coupling to an optical cavity -- demonstrated via the dispersive shift of the resonance of the cavity in presence of the atoms -- and strong Rydberg interactions -- demonstrated via the collective enhancement of Rydberg coupling in the atomic array -- can be achieved in our setup at the same spatial location. Our presented experimental platform opens the path to several new directions, including the realization of quantum network nodes, quantum simulation of long-range interacting, open quantum systems and photonic-state engineering leveraging high-fidelity Rydberg control.
We study the two-dimensional Rydberg atom array in an optical cavity with the help of a variational method and large-scale quantum Monte Carlo simulations. The strong dipole-dipole interactions between Rydberg atoms can make the system exhibit a crystal structure, and the coupling between a two-level atom and a cavity photon mode can result in the formation of a polariton. The interplay between them provides a rich quantum phase diagram including the Mott, solid-1/2, superradiant, and superradiant solid (SRS) phases. As a two-order coexisted phase, the superradiant solid breaks both translational and U(1) symmetries. Different from the fragile SRS phase in a one-dimensional system [Zhang et al., Phys. Rev. Lett. 110, 090402 (2013)], the SRS phase stays in a larger parameter region. Thus, it is more feasible to detect a SRS phase and corresponding quantum criticality in the real system involving dissipations. Our work not only extends the understanding of the light-atom interacting system, but also provides the guidelines and benchmark for the future experiments.
Abstract We investigate the coherent manipulation of interacting Rydberg atoms placed inside a high-finesse optical cavity for the deterministic preparation of strongly coupled light-matter systems. We consider a four-level diamond scheme with one common Rydberg level for N interacting atoms. One side of the diamond is used to excite the atoms into a collective ‘superatom’ Rydberg state using either π -pulses or stimulated Raman adiabatic passage (STIRAP) pulses. The upper transition on the other side of the diamond is used to transfer the collective state to one that is coupled to a field mode of an optical cavity. Due to the strong interaction between the atoms in the Rydberg level, the Rydberg blockade mechanism plays a key role in the deterministic quantum state synthesis of the atoms in the cavity. We use numerical simulation to show that non-classical states of light can be generated and that the state that is coupled to the cavity field is a collective one. We also investigate how different decay mechanisms affect this interacting many-body system. We also analyze our system in the case of two Rydberg excitations within the blockade volume. The simulations are carried out with parameters corresponding to realizable high-finesse optical cavities and alkali atoms like rubidium.
Integrating Rydberg-state control of atom-atom interactions with cavity control of atom-light interactions enables the combination of local entangling operations with photon-mediated long-range coupling, measurement, and communication. Such integration is challenging because electric fields generated by charges on cavity optics and by cavity-stabilizing actuators may disturb Rydberg-state coherence. Here, we couple a Rydberg tweezer array to a high-cooperativity optical cavity, suppressing the electric fields produced by cavity length actuation so that the residual field variation of about 3mV/cm rms does not limit Rydberg coherence. We demonstrate two capabilities that neither system provides alone. First, we use Purcell-enhanced fluorescence to read out atoms directly in the ground-Rydberg basis within 7.5μs, well within the Rydberg-state lifetime, with ground- and Rydberg-state detection infidelities of 3% and 5%, respectively, and with low atom loss. Second, we use Rydberg-Rydberg interactions to control collective light-atom scattering into the cavity mode. Specifically, we drive blockaded Rabi oscillations between a state with two ground-state atoms, which scatter collectively with a superradiant or subradiant rate controlled by the atomic positions, and an entangled state with a single Rydberg excitation, which scatters like a single atom. These capabilities open routes toward networked Rydberg processors, mid-circuit measurements in analog quantum simulators, and many-body quantum optics with entangled emitters coupled collectively to light.