Demonstrating Coherent Quantum Routers for Bucket-Brigade Quantum Random Access Memory on a Superconducting Processor
Sheng Zhang, Yun-Jie Wang, Peng Wang, Ren-Ze Zhao, Xiao-Yan Yang, Ze-An Zhao, Tian-Le Wang, Hai-Feng Zhang, Zhi-Fei Li, Yuan Wu, Hao-Ran Tao, Liang-Liang Guo, Lei Du, Chi Zhang, Zhi-Long Jia, Wei-Cheng Kong, Zhuo-Zhi Zhang, Xiang-Xiang Song, Yu-Chun Wu, Zhao-Yun Chen, Peng Duan

TL;DR
This paper demonstrates coherent quantum routers on a superconducting processor, achieving high fidelity and scalability, which are crucial for practical quantum memory and large-scale quantum computing.
Contribution
The authors experimentally realize quantum routers using a transition composite gate scheme with inherent error mitigation, advancing scalable and coherent QRAM implementation.
Findings
Achieved up to 95.74% fidelity for individual quantum routers
Validated a two-layer quantum routing network with 82.40% average fidelity
Introduced address encoding in non-adjacent qutrit states for error detection
Abstract
Quantum routers (QRouters) are essential components of bucket-brigade quantum random access memory (QRAM), enabling quantum applications such as Grover's search and quantum machine learning. Despite significant theoretical advances, achieving scalable and coherent QRouters experimentally remains challenging. Here, we demonstrate coherent quantum routers using a superconducting quantum processor, laying a practical foundation for scalable QRAM systems. The quantum router at the core of our implementation utilizes the transition composite gate (TCG) scheme, wherein auxiliary energy levels temporarily mediate conditional interactions, substantially reducing circuit depth compared to traditional gate decompositions. Moreover, by encoding routing addresses in the non-adjacent qutrit states and , our design inherently enables eraser-detection capability, providing…
Peer Reviews
No public reviews on file for this paper yet. If you reviewed it on a platform where reviews are public (OpenReview, ICLR, NeurIPS, ICML), you can paste yours below so the community can read it here.
Videos
No videos yet. Explain this paper in a talk, walkthrough, or lecture? Add one.
Taxonomy
TopicsQuantum Computing Algorithms and Architecture · Quantum Information and Cryptography · Quantum-Dot Cellular Automata
