We present QEst, a procedure to systematically generate approximations for quantum circuits to reduce their CNOT gate count. Our approach employs circuit partitioning for scalability with procedures to 1) reduce circuit length using approximate synthesis, 2) improve fidelity by running circuits that represent key samples in the approximation space, and 3) reason about approximation upper bound. Our evaluation results indicate that our approach of "dissimilar" approximations provides close fidelity to the original circuit. Overall, the results indicate that QEst can reduce CNOT gate count by 30-80% on ideal systems and decrease the impact of noise on existing and near-future quantum systems.

中文翻译：

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稳健且资源高效的量子电路近似

我们介绍了 QEst，这是一种系统地生成量子电路近似值以减少其 CNOT 门数的程序。我们的方法采用电路分区来实现可扩展性，以 1) 使用近似合成减少电路长度，2) 通过运行代表近似空间中关键样本的电路来提高保真度，以及 3) 关于近似上限的原因。我们的评估结果表明，我们的“不同”近似方法提供了对原始电路的接近保真度。总体而言，结果表明 QEst 可以将理想系统上的 CNOT 门数减少 30-80%，并减少噪声对现有和近期量子系统的影响。