论文标题
与古典交流的电路编织
Circuit knitting with classical communication
论文作者
论文摘要
量子位的稀缺是在不久的将来实际使用量子计算机的主要障碍。为了解决这个问题，已经开发了各种电路编织技术，以将大量子电路划分为适合较小设备上的子电路，而费用为模拟开销。在这项工作中，我们研究了一种基于非局部门的准整合性模拟的特定电路编织方法，其操作局部在亚电路上起作用。我们研究这些本地量子计算机之间的经典通信是否可以提供帮助。我们通过证明包含连接两个电路零件的$ N $非本地CNOT门的电路来提供一个积极的答案，如果一个允许经典信息交换，则可以将模拟开销从$ O（9^n）$减少到$ O（4^n）$。对于一般的Clifford门，可以获得类似的改进，至少在受限的形式下，对于其他门（例如受控旋转门）。
The scarcity of qubits is a major obstacle to the practical usage of quantum computers in the near future. To circumvent this problem, various circuit knitting techniques have been developed to partition large quantum circuits into subcircuits that fit on smaller devices, at the cost of a simulation overhead. In this work, we study a particular method of circuit knitting based on quasiprobability simulation of nonlocal gates with operations that act locally on the subcircuits. We investigate whether classical communication between these local quantum computers can help. We provide a positive answer by showing that for circuits containing $n$ nonlocal CNOT gates connecting two circuit parts, the simulation overhead can be reduced from $O(9^n)$ to $O(4^n)$ if one allows for classical information exchange. Similar improvements can be obtained for general Clifford gates and, at least in a restricted form, for other gates such as controlled rotation gates.
