Department of Electrical and Computer Engineering and Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, Maryland 20742, USA.
Joint Quantum Institute, University of Maryland, College Park, Maryland 20742, USA.
Phys Rev Lett. 2019 Oct 11;123(15):150503. doi: 10.1103/PhysRevLett.123.150503.
Temporal multiplexing provides an efficient and scalable approach to realize a quantum random walk with photons that can exhibit topological properties. But two-dimensional time-multiplexed topological quantum walks studied so far have relied on generalizations of the Su-Shreiffer-Heeger model with no synthetic gauge field. In this work, we demonstrate a two-dimensional topological quantum random walk where the nontrivial topology is due to the presence of a synthetic gauge field. We show that the synthetic gauge field leads to the appearance of multiple band gaps and, consequently, a spatial confinement of the quantum walk distribution. Moreover, we demonstrate topological edge states at an interface between domains with opposite synthetic fields. Our results expand the range of Hamiltonians that can be simulated using photonic quantum walks.
时间复用提供了一种高效且可扩展的方法来实现具有拓扑性质的光子量子漫步。但是，迄今为止研究的二维时间复用拓扑量子漫步依赖于没有合成规范场的 Su-Shreiffer-Heeger 模型的推广。在这项工作中，我们展示了一种二维拓扑量子随机漫步，其中非平凡的拓扑结构是由于存在合成规范场。我们表明，合成规范场导致多个能带隙的出现，从而导致量子漫步分布的空间限制。此外，我们在具有相反合成场的域之间的界面上演示了拓扑边缘状态。我们的结果扩展了可以使用光子量子漫步模拟的哈密顿量的范围。
