Roy F A, Romeiro J H, Koch L, Tsitsilin I, Schirk J, Glaser N J, Bruckmoser N, Singh M, Haslbeck F X, Huber G B P, Krylov G, Marx A, Pfeiffer F, Schneider C M F, Schweizer C, Wallner F, Bunch D, Richard L, Södergren L, Liegener K, Werninghaus M, Filipp S
Walther-Meißner-Institut, Bayerische Akademie der Wissenschaften, Garching, Germany.
Theoretical Physics, Saarland University, Saarbrücken, Germany.
Nat Commun. 2025 Mar 18;16(1):2660. doi: 10.1038/s41467-025-57818-2.
As quantum information technologies advance, challenges in scaling and connectivity persist, particularly the need for long-range qubit connectivity and efficient entanglement generation. Perfect State Transfer enables time-optimal state transfer between distant qubits using only nearest-neighbor couplings, enhancing device connectivity. Moreover, the transfer protocol results in effective parity-dependent non-local interactions, extending its utility to entanglement generation. Here, we experimentally demonstrate Perfect State Transfer and multi-qubit entanglement generation on a chain of six superconducting transmon qubits with tunable couplers, controlled via parametric drives. By simultaneously activating and engineering all couplings, we implement the transfer for up to six qubits, verifying single-excitation dynamics for different initial states. Extending the protocol to multiple excitations, we confirm its parity-dependent nature, where excitation number controls the phase of the transferred state. Finally, leveraging this property, we prepare a Greenberger-Horne-Zeilinger state using a single transfer operation, showcasing potential of Perfect State Transfer for efficient entanglement generation.
随着量子信息技术的发展，在规模扩展和连接性方面的挑战依然存在，尤其是对远程量子比特连接性和高效纠缠生成的需求。完美态转移仅使用最近邻耦合就能在远距离量子比特之间实现时间最优的态转移，增强了设备的连接性。此外，转移协议会产生有效的奇偶依赖非局域相互作用，将其应用扩展到纠缠生成。在此，我们通过参数驱动控制，在一个带有可调耦合器的六个超导传输子量子比特链上，通过实验演示了完美态转移和多量子比特纠缠生成。通过同时激活和设计所有耦合，我们实现了多达六个量子比特的转移，验证了不同初始态的单激发动力学。将该协议扩展到多个激发态，我们证实了其奇偶依赖性质，即激发数控制转移态的相位。最后，利用这一特性，我们通过单次转移操作制备了一个格林伯格 - 霍恩 - 蔡林格态，展示了完美态转移在高效纠缠生成方面的潜力。
