1. Long-Range $ZZ$ Interaction via Resonator-Induced Phase in Superconducting Qubits
- Author
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Deng, Xiang, Zheng, Wen, Liao, Xudong, Zhou, Haoyu, Ge, Yangyang, Zhao, Jie, Lan, Dong, Tan, Xinsheng, Zhang, Yu, Li, Shaoxiong, and Yu, Yang
- Subjects
Quantum Physics - Abstract
Superconducting quantum computing emerges as one of leading candidates for achieving quantum advantage. However, a prevailing challenge is the coding overhead due to limited quantum connectivity, constrained by nearest-neighbor coupling among superconducting qubits. Here, we propose a novel multimode coupling scheme using three resonators driven by two microwaves, based on the resonator-induced phase gate, to extend the $ZZ$ interaction distance between qubits. We demonstrate a CZ gate fidelity exceeding 99.9\% within 160 ns at free spectral range (FSR) of 1.4 GHz, and by optimizing driving pulses, we further reduce the residual photon to nearly $10^{-3}$ within 100 ns at FSR of 0.2 GHz. These facilitate the long-range CZ gate over separations reaching sub-meters, thus significantly enhancing qubit connectivity and making a practical step towards the scalable integration and modularization of quantum processors. Specifically, our approach supports the implementation of quantum error correction codes requiring high connectivity, such as low-density parity check codes that paves the way to achieving fault-tolerant quantum computing., Comment: 7 pages, 4 figures
- Published
- 2024