AI 中文总结
本文针对云量子计算异构计费下的成本感知比较难题，开展跨提供商量子电路保真度测量，提出整合KL散度、shots数与货币成本的QFC指标，发现成本感知排名与纯保真度排名存在差异，计费模型影响QFC随shots数的变化。
AI 中文摘要
可通过云访问的量子计算使得硬件比较不仅成为物理基准，也成为实际采购决策。量子计算机的成本感知比较仍未得到充分探索，且由于不同云基量子计算提供商提供的异构计费模式，难以开展此类比较。本文为实现量子计算机的价格感知比较作出两项主要贡献：其一，开展了跨提供商的量子电路执行保真度测量研究，涵盖四个云访问路径（亚马逊网络服务（AWS）云、IBM量子运行时（IBM）云、IQM共振（IQM）云以及牛津量子电路（OQC）云）中的14个云量子处理单元（QPU）访问路径条目（12个不同的物理QPU）；其二，提出并分析了一种成本感知分数——量子保真度-成本比（Quantum Fidelity-per-Cost，QFC），该指标在已记录的计费模型下，将理想输出分布的库尔贝克-莱布勒（Kullback--Leibler，KL）散度、 shots数（采样次数）以及货币成本整合为一个指标。本文的主要实证观察结果为：成本感知排名与纯基于保真度的量子计算机评估结果存在差异，当用户在选择时考虑价格因素，会与仅基于保真度的选择不同，选用不同的量子计算后端；该排名在指标重新加权下保持稳定，且设备的计费模型而非其硬件，决定了其分数随shots数的变化情况；报告的QFC值会随新机器上线或提供商修改价格而发生变化。
英文摘要
Cloud-accessible quantum computing has made hardware comparison not only a physics benchmark but also a practical purchasing decision. Cost-aware comparison of quantum computers remains underexplored and is difficult to do under the heterogeneous billing models offered by various cloud-based quantum computing providers. This paper makes two main contributions to enable price-aware comparison of quantum computers. First, this work presents a cross-provider measurement study of quantum circuit execution fidelity spanning 14 cloud QPU access-path entries (12 distinct physical QPUs) across four cloud access paths: Amazon Web Services (AWS) cloud, IBM Quantum Runtime (IBM) cloud, IQM Resonance (IQM) cloud, and Oxford Quantum Circuits (OQC) cloud. Second, this work proposes and analyzes a cost-aware score, Quantum Fidelity-per-Cost (QFC), which combines Kullback--Leibler (KL) divergence from an ideal output distribution, shot count, and monetary cost into one possible metric under a documented billing model. The main empirical observation from this work is that cost-aware ranking can differ from purely fidelity-based evaluation of quantum computers, and that users may select different quantum computing backends when they consider price in their selection, as opposed to selection based on fidelity alone. This work shows that the ranking is stable under reweighting of the metric, and that a device's billing model, not its hardware, governs how its score scales with shot count. Reported QFC values change as new machines come online or as providers revise their prices.
Comments7 pages, 4 figures, 3 tables. Accepted at IEEE International Conference on Quantum Computing and Engineering (QCE) 2026
