Hefei National Laboratory for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026, China.
Shanghai Branch, CAS Center for Excellence and Synergetic Innovation Center in Quantum Information and Quantum Physics, 10 University of Science and Technology of China, Shanghai 201315, China.
Phys Rev Lett. 2019 Mar 22;122(11):110501. doi: 10.1103/PhysRevLett.122.110501.
We report the preparation and verification of a genuine 12-qubit entanglement in a superconducting processor. The processor that we designed and fabricated has qubits lying on a 1D chain with relaxation times ranging from 29.6 to 54.6 μs. The fidelity of the 12-qubit entanglement was measured to be above 0.5544±0.0025, exceeding the genuine multipartite entanglement threshold by 21 statistical standard deviations. After thermal cycling, the 12-qubit state fidelity was further improved to be above 0.707±0.008. Our entangling circuit to generate linear cluster states is depth invariant in the number of qubits and uses single- and double-qubit gates instead of collective interactions. Our results are a substantial step towards large-scale random circuit sampling and scalable measurement-based quantum computing.
我们报告了在超导处理器中制备和验证真正的 12 量子比特纠缠态的情况。我们设计和制造的处理器中的量子比特位于一维链上，弛豫时间范围为 29.6 至 54.6 μs。通过测量，12 量子比特纠缠的保真度超过 0.5544±0.0025，超过了真正的多体纠缠阈值 21 个标准差。经过热循环后，12 量子比特状态的保真度进一步提高到 0.707±0.008。我们用于生成线性簇态的纠缠电路在量子比特数量上具有不变的深度，并且使用单量子比特和双量子比特门而不是集体相互作用。我们的研究结果是迈向大规模随机电路采样和可扩展基于测量的量子计算的重要一步。
