Classical simulations of quantum circuits are limited in both space and time when the qubit count is above 50, the realm where quantum supremacy reigns. However, recently, for the low depth circuit with more than 50 qubits, there are several methods of simulation proposed by teams at Google and IBM. Here, we present a scheme of simulation which can extract a large amount of measurement outcomes within a short time, achieving a 64-qubit simulation of a universal random circuit of depth 22 using a 128-node cluster, and 56- and 42-qubit circuits on a single PC. We also estimate that a 72-qubit circuit of depth 23 can be simulated in about 16 h on a supercomputer identical to that used by the IBM team. Moreover, the simulation processes are exceedingly separable, hence parallelizable, involving just a few inter-process communications. Our work enables simulating more qubits with less hardware burden and provides a new perspective for classical simulations.

当量子位计数超过 50 时，量子电路的经典模拟在空间和时间上都受到限制，这是量子至上的领域。然而，最近，对于超过50个量子比特的低深度电路，谷歌和IBM的团队提出了几种模拟方法。在这里，我们提出了一种可以在短时间内提取大量测量结果的仿真方案，使用 128 节点集群实现了深度为 22 的通用随机电路的 64 量子比特仿真，以及 56 和 42 量子比特单台 PC 上的电路。我们还估计，在与 IBM 团队使用的超级计算机相同的超级计算机上，可以在大约 16 小时内模拟深度为 23 的 72 量子位电路。此外，模拟过程是高度可分离的，因此是可并行的，只涉及一些进程间通信。