Quantum optics using Rydberg polaritons

最小量的光被称为光子。虽然光子数量很多，但逐个控制它们仍然具有挑战性。如果我们能够获得更多的控制，我们可以在许多领域取得巨大的进步，包括成像，传感，计算和通信。在这个项目中，我们的目标是获得更多的控制单个光子使用一种特殊类型的原子被称为里德伯原子。在里德伯原子中，一个电子被激发到一个平均离原子核很远的状态。在这种里德伯态下，原子的性质被大大夸大了。特别是，它对附近的里德伯原子变得非常敏感。在过去的十年里，在达勒姆，我们已经展示了如何将里德伯原子之间的这种敏感性映射成光子之间的强相互作用。这个被称为里德伯量子光学的想法，导致了有史以来光子之间最强的相互作用。里德伯量子光学之旅的下一步是使这个系统更有用。我们提出的一个主要的实用性的步骤变化是联合收割机结合里德堡量子光学的显着特点与集成光子学的力量。我们将使用基于光纤耦合芯片的架构来按需投射单个光子并控制光子之间的相互作用。此外，我们将展示这些设备如何与基于冷原子的量子存储器接口。另一个重要的挑战，使里德堡光子学技术相关的是使基础物理和潜在的设备更快地工作。目前，速度限制在每秒Mbits的范围内。在这个项目中，我们将探索当我们尝试将其扩展到每秒千兆位范围时会发生什么。除了提高数据速率，更快的速度还有另一个好处，那就是我们对原子运动的敏感度降低了，而原子运动目前是降低效率的过程之一。这项提案中展示的步骤将有助于实现量子互联网的梦想。

The smallest amount of light is known as a photon. Although photons are plentiful, controlling them one-by-one remains challenging. If we could gain more control we could make tremendous advances in many areas including imaging, sensing, computing and communications.In this project, we aim to gain more control over individual photons using a special type of atom known as a Rydberg atom. In a Rydberg atom, one electron is excited to a state where it is on average very far from the nucleus. In this Rydberg state, the atom has greatly exaggerated properties. In particular, it becomes extremely sensitive to nearby Rydberg atoms. Over the last decade in Durham, we have shown how to map this sensitivity between Rydberg atoms into a strong interaction between photons. This idea, known as Rydberg quantum optics, has resulted in the strongest interaction between photons ever demonstrated.The next steps on this Rydberg quantum optics journey is to make this system more useful. A major step change in utility that we are proposing is to combine the remarkable features of Rydberg quantum optics with the power of integrated photonics. We will use a fibre coupled chip-based architecture to project single photons on demand and control the interactions between photons. In addition, we will show how these devices can be interfaced with cold atom based quantum memories. Another important challenge to make Rydberg photonics technologically relevant is to make underlying physics and potential devices work faster. Currently the speed limit is in the range of Mbits per second. In this project, we will explore what happens when we try to extend this into the Gbits per second range. As well as increase data rates, going faster also has another advantage in that we become less sensitive to atomic motion which is currently one of the processes that degrade efficiency.The steps demonstrated in this proposal will facilities significant progress towards the dream of a quantum internet.