用哈密顿量导出的克利福德变换减少纠缠
Reducing entanglement with a Hamiltonian derived Clifford transformation
浏览论文内容
中文总结 AI 辅助
研究利用Q-Cliff算法生成化学系统基态的高效近似，该算法精度在MP2和CISD之间，计算量为\(O(N^6)\)。通过DMRG计算减少量子比特纠缠，改进算法生成低深度且CNOT高效的电路，为经典和量子算法提供新工具。
中文摘要 AI 辅助
最近（《物理学报》，100(10):105401，2025），一种算法被引入，它能从量子比特耦合簇（QCC）算法确定性地生成克利福德变换，即Q-Cliff（QCC + 克利福德）。此前表明Q-Cliff可用于生成硬件高效版的QCC假设。本文研究并改进这些技术，表明Q-Cliff可用于生成化学系统基态的高效经典和量子近似。该算法生成一种高效变分方法，精度一般在MP2和CISD之间，计算量为\(O(N^6)\)。通过DMRG计算表明量子比特间纠缠显著减少，给定键维度下精度可大幅提高（达一个数量级）。最后改进算法生成低深度且CNOT高效的电路，能量评估次数与先进的VQE算法相当。所有这些结果表明这种哈密顿量导出的克利福德变换应成为许多经典和量子算法的工具。
英文摘要
Recently (Physica Scripta, 100(10):105401, 2025), an algorithm was introduced that deterministically generates a Clifford transformation from the Qubit Coupled Cluster (QCC) algorithm which we call Q-Cliff (QCC+Clifford). There, it was shown that Q-Cliff could be utilized to generate a hardware efficient version of the QCC ansatz. Here, we examine and refine these techniques and show that Q-Cliff can be utilized to generate efficient classical and quantum approximations to the ground states of chemical systems. The algorithm generates an efficient variational method that generally has accuracy between MP2 and CISD with $O(N^6)$. Furthermore, we show through DMRG calculations that the entanglement between qubits is reduced significantly and therefore the accuracy for a given bond dimension can be vastly improved (up to an order of magnitude). Finally, we refine the previously reported algorithm to generate low-depth and CNOT efficient circuits that can be optimized with a comparable number of energy evaluations to state-of-the-art VQE algorithms. All these results show that this Hamiltonian derived Clifford transformation should be a tool used for many classical and quantum algorithms.
