Qubit mapping for NISQ superconducting quantum computers is essential to fidelity and resource utilization. The existing qubit mapping schemes meet challenges, e.g., crosstalk, SWAP overheads, diverse device topologies, etc., leading to qubit resource underutilization and low fidelity in computing results. This article introduces QuCloud+, a new qubit mapping scheme that tackles these challenges. QuCloud+ has several new designs. (1) QuCloud+ supports single/multi-programming quantum computing on quantum chips with 2D/3D topology. (2) QuCloud+ partitions physical qubits for concurrent quantum programs with the crosstalk-aware community detection technique and further allocates qubits according to qubit degree, improving fidelity, and resource utilization. (3) QuCloud+ includes an X-SWAP mechanism that avoids SWAPs with high crosstalk errors and enables inter-program SWAPs to reduce the SWAP overheads. (4) QuCloud+ schedules concurrent quantum programs to be mapped and executed based on estimated fidelity for the best practice. Experimental results show that, compared with the existing typical multi-programming study [12], QuCloud+ achieves up to 9.03% higher fidelity and saves on the required SWAPs during mapping, reducing the number of CNOT gates inserted by 40.92%. Compared with a recent study [30] that enables post-mapping gate optimizations to further reduce gates, QuCloud+ reduces the post-mapping circuit depth by 21.91% while using a similar number of gates.

NISQ 超导量子计算机的量子位映射对于保真度和资源利用率至关重要。现有的量子位映射方案面临串扰、SWAP开销、不同的设备拓扑等挑战，导致量子位资源利用不足和计算结果保真度低。本文介绍了 QuCloud+，这是一种解决这些挑战的新量子位映射方案。QuCloud+有多项新设计。(1) QuCloud+支持2D/3D拓扑量子芯片上的单/多编程量子计算。（2）QuCloud+通过串扰感知社区检测技术对并发量子程序的物理量子位进行划分，并进一步根据量子位度分配量子位，提高保真度和资源利用率。(3) QuCloud+包含X-SWAP机制，避免高串扰错误的SWAP，并启用程序间SWAP以减少SWAP开销。(4) QuCloud+根据最佳实践的估计保真度来调度要映射和执行的并发量子程序。实验结果表明，与现有典型的多编程研究[12]相比，QuCloud+的保真度提高了9.03%，并节省了映射过程中所需的SWAP，减少了40.92%插入的CNOT门数量。与最近的一项研究[30]相比，该研究能够通过后映射门优化来进一步减少门，QuCloud+在使用相似门数的情况下将后映射电路深度减少了21.91%。