里德堡原子多体相互作用的研究进展

Research progress of Rydberg many-body interaction

多体量子系统的相互作用是研究量子信息科学必须要解决的瓶颈性问题之一.里德堡(Rydberg)原子具有很大的电偶极矩,使得它可以实现长程的相互作用,为研究多体量子物理提供了有力的技术手段.因而Rydberg原子多体系统是多体相互作用探究的理想平台,Rydberg原子多体相互作用的研究对多体量子系统的相互作用的性质研究和应用探究有着重要意义.本文综述了关于Rydberg原子多体相互作用方面的研究,介绍了由Rydberg原子的多体相互作用引起的Rydberg阻塞效应、Rydberg原子多体系统拉比频率的变化以及Rydberg原子多体系统呈现的特别的空间构型;同时介绍了利用Rydberg原子多体相互作用实现一些应用的工作,如实现单光子源、量子存储、实时单原子成像以及量子模拟等,并讨论了Rydberg原子多体系统的研究方向和应用前景.

The interaction of many-body quantum system is a critical problem to be solved in the field of quantum information science. Rydberg atoms have large dipole moment, enabling them to interact with others in a long range, thereby offering us a powerful tool for studying many-body quantum physics. Meanwhile, atoms in the ground state are stable, which makes it easy to manipulate them. Therefore, Rydberg-atom many-body system is an ideal platform for studying the interaction of many-body quantum system. Studies of Rydberg-atom manybody system may contribute to understanding the properties of many-body system and putting the interaction of many-body quantum system into practical applications. In this review, we introduce some studies of properties of interaction of Rydberg-atom many-body system, including the Rydberg excitation blockade, the variation of Rabi frequencies of the many-body system and special spatial distribution of Rydberg atoms in a many-body system. Firstly, the Rydberg excitation blockade, the most important property in the Rydberg-atom many-body system, indicates that atoms’ excitation will be suppressed in a certain range around one Rydberg excitation because the interaction between the Rydberg excitation and atoms leads the energy level to shift so that atoms cannot be excited by the same pulse. Secondly, there is a collective Rabi frequency in the system,which is proportional to the square of the number of atoms in the suppressed area. And additionally, because of the Rydberg blockade effect, Rydberg excitations in the ensemble cannot be at casual positions but a regular distribution is formed. Besides the studies of properties, several researches on the applications of interaction of Rydberg-atom many-body system are introduced, including single-photon source, quantum storage, single-atom imaging, quantum simulation, etc. These applications contribute to the development of quantum community and quantum computing, which may bring us a quantum-technology time. Finally, we discuss the future development of Rydberg-atom many-body system and its further applications. Further development includes the development of many-body system with a larger number of atoms, the development of many-body system of atoms with more than one electron, and some other specific subjects based on many-system, such as Rydberg dimer and topological phase. Also some promising applications such as in studying optimization problem by quantum annealing, may become true.