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Pei-Yao Song

Publications and source records attributed to Pei-Yao Song.

4 recordsLinked to original sources

Cascaded Rydberg antiblockade: Multi-atom excitation dynamics and entanglement

We propose a cascaded Rydberg antiblockade (RAB) regime via a Floquet modulation in four fully connected interacting atoms, which establishes a new synthetic dimension, Dicke-state lattice (DSL), in the space of collective spin excitations. By applying a global periodic driving, we synthesize an effective Hamiltonian that enables perfect state transfer across the five-site DSL with multiple programmable pathways from stepwise nearest-neighbor jumps to a single-step transition. This DSL platform further allows us to simulate a dynamic Su-Schrieffer-Heeger model, where soft quantum control is employed to achieve topologically inspired full RAB $|0000\rangle \to |1111\rangle$ with enhanced robustness against disorder. Moreover, by incorporating the shortcut to adiabaticity technique, we generate high-fidelity entangled twin-Fock and Greenberger-Horne-Zeilinger states on the four atoms within sub-microsecond timescales, outperforming the speed limits of conventional adiabatic protocols. Our work demonstrates a flexible and programmable synthetic dimension for quantum simulation and multipartite entanglement engineering in Rydberg atom arrays, paving the way for the future development of quantum information processing.

quant-ph

Global adiabatic criterion for fast topological photon transfer in Fock-state lattices

Topological state transfer in Fock-state lattices has been demonstrated with high speed using sinusoidal profiles of coupling, yet the underlying reason has remained unclear. A global adiabatic criterion (GAC) is developed to bound the infidelity by the mean and variance of the nonadiabatic factor. The GAC reveals that the key to fast transfer is not a constant energy gap but the vanishing nonadiabaticity variance. For power-law coupling profiles, the variance vanishes only for the sinusoidal shape, which is thus globally optimal. Incorporating experimental decoherence parameters, it is predicted that the optimal transfer duration for a five-photon state is 161 ns, far shorter than 600 ns used in the experiment, reducing time by over 73% while increasing transferred photons by 29%. The optimal duration follow a simple linear scaling with photon number, providing a practical guideline. Through constructing an alternative constant-gap coupling family, it is confirmed that a constant gap alone is not sufficient for fast topological photon transfer. The essential condition is uniformity of nonadiabaticity. This work offers a rigorous explanation for the observed speed and a general framework for fast topological photonics engineering.

quant-ph

Topological Quantum Transducers in a Hybrid Rydberg Atom System

We propose a topological transport platform for microwave-to-optical conversion at the single-photon level in a Rydberg atom-cavity setting. This setting leverages a hybrid dual-mode Jaynes-Cummings (JC) configuration, where a microwave resonator couples an optical cavity mediated by a Rydberg atom ensemble. Our scheme uniquely enables the formation of Fock-state lattices (FSLs), where photon hopping rates depend on photon numbers in individual sites. We identify an inherent zero-energy mode corresponding to the dark state of the dual-mode JC model. This enables to build a high-efficiency single-photon transducer, which realizes topologically protected photon transport between the microwave and optical modes. Crucially, we show analytically that the FSL features continuous variations of the winding number. Our work establishes a robust mechanism for efficient quantum transduction in synthetic dimensions and opens avenues for exploring topological physics with continuous winding numbers in the atom-cavity system.

quant-ph

Rydberg Superatom Interface for Topological Microwave-to-Optical Photon Conversion in Fock-State Lattices

Microwave-to-optical conversion (MTOC) of single photons plays a pivotal role in bridging quantum devices across different frequency domains, but faces challenges in maintaining efficiency and robustness against fluctuations and dissipation in hybrid quantum systems. Here, we propose a topologically protected MTOC scheme mediated by a Rydberg superatom to address these limitations. By constructing cross-linked Fock-state lattices (FSLs) through a dual-mode Jaynes-Cummings (JC) architecture, we map the effective hybrid system onto an extended Su-Schrieffer-Heeger~(SSH) model with tunable hopping rates. Photon-number--dependent property of hopping rates triggers a topological phase transition in the extended SSH chain, converting the defect mode into a topological channel that directionally pumps photons between microwave and optical cavities. This mechanism leverages Rydberg blockade-enhanced photon-superatom couplings to establish a robust energy transfer channel, achieving high-efficiency photon conversion under realistic decoherence. Our theoretical framework demonstrates how topological protection synergizes with Rydberg-mediated light-matter interactions to realize a robust quantum transducer, providing a scalable platform for noise-resilient quantum networks and frequency-multiplexed quantum interfaces.

quant-ph