近日，浙江大学尹建伟团队研究了“桶旅”架构量子随机存取存储器。2026年3月16日，《自然—物理学》杂志发表了这一成果。
量子随机存取存储器（QRAM）使量子计算机能够高效访问经典数据，是许多量子算法实现量子加速的先决条件。尽管已有各种方案提出，但QRAM的实验实现并不多见。
研究组利用超导量子处理器实现了一种基于电路的“桶旅”架构（bucket-brigade）QRAM，该架构利用量子路由器组成的二叉树结构来实现对存储信息的高效寻址。为了便于实验实现，研究组为量子路由器引入了一种高效的门分解方案，与传统的受控交换门实现相比，该方案有效降低了QRAM电路的深度。
研究组进一步提出了一种误差缓解方法，以提高QRAM的查询保真度。利用这些技术，他们成功实验实现了用于寻址四位和八位经典比特的QRAM架构，查询保真度分别高达0.809 ± 0.025和0.604 ± 0.005。此外，还研究了QRAM实现中的误差传播机制和可扩展性，为“桶旅”架构的抗噪性提供了实验证据。该结果凸显了超导量子处理器在实现可扩展QRAM架构方面的潜力。
附：英文原文
Title: A bucket-brigade quantum random access memory
Author: Shen, Fanhao, Ji, Yujie, Xiang, Debin, Wang, Yanzhe, Wang, Ke, Zhang, Chuanyu, Zhang, Aosai, Zou, Yiren, Gao, Yu, Cui, Zhengyi, Liu, Gongyu, Yang, Jianan, Han, Yihang, Deng, Jinfeng, Wang, Anbang, Zhang, Zhihong, Li, Hekang, Guo, Qiujiang, Zhang, Pengfei, Song, Chao, Lu, Liqiang, Wang, Zhen, Yin, Jianwei
Issue&Volume: 2026-03-16
Abstract: Quantum random access memory (QRAM) enables efficient access to classical data for quantum computers and is a prerequisite for many quantum algorithms in achieving quantum speed-up. Despite various proposals, there have not been many experimental realizations of QRAM. Here we use a superconducting quantum processor to implement a circuit-based bucket-brigade QRAM, which uses a binary tree of quantum routers to enable efficient addressing of the stored information. To facilitate the experimental implementation, we introduce an efficient gate decomposition scheme for quantum routers, which effectively reduces the depth of the QRAM circuit compared with the conventional controlled-SWAP implementation. We further propose an error mitigation method to improve the query fidelity of the QRAM. With these techniques, we are able to experimentally implement the QRAM architectures for addressing four and eight classical bits, achieving query fidelities up to 0.809 ±0.025 and 0.604 ±0.005, respectively. Additionally, we study the error propagation mechanism and the scalability of our QRAM implementation, which provides experimental evidence for the noise resilience of the bucket-brigade architecture. Our results highlight the potential of superconducting quantum processors for realizing a scalable QRAM architecture.
DOI: 10.1038/s41567-026-03218-2
Source: https://www.nature.com/articles/s41567-026-03218-2