一句话：提出一种无需辅助量子比特编译条件量子门的方案，门数仅为先前最佳方案的三分之一。
本文研究条件量子门的编译问题：如何将多量子比特条件编译为线性数量的两量子比特条件，同时避免使用辅助量子比特。使用辅助量子比特可较直接实现，但会消耗额外资源；作者提出一种无需辅助量子比特的编译方案，并显著减少门数。与先前不使用辅助量子比特的最佳方案相比，该方案所需门数仅为其三分之一，这对实际应用至关重要。实验表明，若干量子线路优化器对先前最佳方案编译出的代码影响很小，说明需要新方案；在 Grover 算法和量子行走上的实验还显示，新方案能显著提升编译代码的可靠性。
We present a compilation scheme for conditional quantumgates. Our scheme compiles amulti-qubit conditional to a linear number of two-qubit conditionals. This can be done straightforwardly with helper qubits, but we show how to do it without using helper qubits and with much fewer gates than in previous work. Specifically, our scheme requires 1/3 as many gates as the previous best scheme without using helper qubits, which is essential for practical use. Our experiments show that several quantum-circuit optimizers have little impact on the compiled code from the previous best scheme, confirming the need for our new scheme. Our experiments with Grover’s algorithm and quantum walk also show that our scheme has a major impact on the reliability of the compiled code.
@article{HuangP24,
title = {Compiling Conditional Quantum Gates without Using Helper Qubits},
author = {Keli Huang and Jens Palsberg},
journal = {Proceedings of the ACM on Programming Languages},
volume = {8},
number = {PLDI},
year = {2024},
doi = {10.1145/3656436}
}