Minimizing the use of CNOT gates in quantum state preparation is a crucial step in quantum compilation, as they introduce coupling constraints and more noise than single-qubit gates. Reducing the number of CNOT gates can lead to more efficient and accurate quantum computations. However, the lack of compatibility to model superposition and entanglement challenges the scalability and optimality of CNOT optimization algorithms on classical computers. In this paper, we propose an effective state preparation algorithm using an exact CNOT synthesis formulation. Our method represents a milestone as the first design automation algorithm to surpass manual design, reducing the best CNOT numbers to prepare a Dicke state by 2x. For general states with up to 20 qubits, our method reduces the CNOT number by 9% and 32% for dense and sparse states, on average, compared to the latest algorithms.

翻译：在量子态制备中最小化CNOT门的使用是量子编译中的关键步骤，因为CNOT门会引入耦合约束并比单量子比特门产生更多噪声。减少CNOT门数量可以带来更高效和精确的量子计算。然而，模型叠加态和纠缠态的兼容性不足，使得CNOT优化算法在经典计算机上的可扩展性和最优性面临挑战。本文提出了一种使用精确CNOT综合公式的高效量子态制备算法。我们的方法标志着首个超越人工设计的设计自动化算法里程碑，将制备Dicke态的最佳CNOT数量减少至原来的二分之一。对于最多20个量子比特的一般量子态，与最新算法相比，我们的方法平均将稠密态和稀疏态的CNOT数量分别减少了9%和32%。