Department of Physics, Oklahoma State University, Stillwater, Oklahoma 74078-3072, USA.
ITP, Heidelberg University, Philosophenweg 12, 69120 Heidelberg, Germany.
Phys Rev Lett. 2018 Aug 17;121(7):070402. doi: 10.1103/PhysRevLett.121.070402.
We present a discrete-time, one-dimensional quantum walk based on the entanglement between the momentum of ultracold rubidium atoms (the walk space) and two internal atomic states (the "coin" degree of freedom). Our scheme is highly flexible and can provide a platform for a wide range of applications such as quantum search algorithms, the observation of topological phases, and the realization of walks with higher dimensionality. Along with the investigation of the quantum-to-classical transition, we demonstrate the distinctive features of a quantum walk and contrast them to those of its classical counterpart. Also, by manipulating either the walk or coin operator, we show how the walk dynamics can be steered or even reversed.
我们提出了一种基于超冷铷原子动量（行走空间）和两个内部原子态（“硬币”自由度）之间纠缠的离散时间、一维量子行走。我们的方案具有高度的灵活性，可以为量子搜索算法、拓扑相观测和更高维行走的实现等广泛的应用提供平台。在研究量子到经典的转变的同时，我们展示了量子行走的独特特征，并将其与经典对应物进行了对比。此外，通过操纵行走或硬币算子，我们展示了如何引导甚至反转行走动力学。
