发表机构
National Taiwan University; Center for Theoretical Physics, National Taiwan University; National Center for Theoretical Sciences; Chung Yuan Christian University(国立台湾大学; 国立台湾大学理论物理中心; 国家理论科学中心; 中原大学)
机构由 AI 辅助整理,请以论文原文为准。AI 中文总结
针对标准狄拉克元胞自动机在有限格点上因相位匹配抑制干涉现象的问题,提出分裂步方案,在固定空间离散下实现连续时间演化,并在IBM量子处理器上验证了其有效性。
AI 中文摘要
狄拉克元胞自动机(DCA)为模拟狄拉克动力学提供了一个框架,然而空间和时间分辨率之间的刚性耦合会在有限格点上引入人为的相位匹配对称性,从而抑制诸如颤动(Zitterbewegung)之类的干涉现象。在本工作中,我们提出了一种分裂步狄拉克元胞自动机(SDCA),它能够在固定空间离散化下实现连续时间的狄拉克演化。通过在动量表示中采用Trotter化的分步方案,SDCA打破了标准DCA中存在的相位匹配消除,并恢复了连续时间极限的干涉动力学。我们通过解析和数值研究对SDCA进行了基准测试,并展示了其在IBM量子处理器上的实现。尽管更精细的时间分辨率需要增加电路深度,NISQ实现仍再现了连续时间模型的特征速度振荡和纠缠熵动力学。我们进一步研究了硬件拓扑权衡和量子傅里叶变换(QFT)的动态电路实现,强调了门误差、测量和前馈延迟之间的竞争效应。这些结果表明,SDCA提供了一个实用框架,在保持固定空间量子寄存器的同时提高时间分辨率,使得在近期量子设备上探索相对论量子动力学成为可能。
英文摘要
Dirac Cellular Automata (DCA) provide a framework for simulating Dirac dynamics, yet the rigid coupling between spatial and temporal resolutions can introduce artificial phase-matching symmetries on finite grids that suppress interference phenomena such as Zitterbewegung. In this work, we propose a Split-Step Dirac Cellular Automaton (SDCA) that enables continuous-time Dirac evolution at fixed spatial discretization. By employing a Trotterized fractional-step scheme in the momentum representation, SDCA breaks the phase-matching cancellation present in the standard DCA and recovers the interference dynamics of the continuous-time limit. We benchmark the SDCA through analytical and numerical studies and demonstrate its implementation on IBM Quantum processors. Despite the increased circuit depth required for finer temporal resolution, the NISQ implementation reproduces the characteristic velocity oscillations and entanglement-entropy dynamics of the continuous-time model. We further investigate hardware-topology trade-offs and dynamic circuit implementations of the Quantum Fourier Transform (QFT), highlighting the competing effects of gate errors, measurement, and feed-forward latency. These results demonstrate that SDCA provides a practical framework for improving temporal resolution while maintaining a fixed spatial quantum register, enabling the exploration of relativistic quantum dynamics on near-term quantum devices.