Ultracold quantum memories

量子技术已经展示了在通信、计量和计算方面进行巨大技术改进的潜力。尽管利用量子技术的方法多种多样，但基于光编码信息的光子技术是一种令人兴奋的范例。光子可以在复杂的自由空间或光纤网络中以最小的退相干进行传输。这是由于它们与其他场或粒子的相互作用很弱。虽然这是一个理想的特征，但它也成为一个技术挑战，因为这导致了对量子信息处理的概率协议的需求。近几十年来，激光科学和原子物理的不断进步使得在原子蒸气中按需存储和检索光子信息成为可能，从而从概率协议过渡到确定性协议。这被命名为光子量子存储器。这项技术中的一个重要限制因素是由于存储光子信息的原子的运动，导致存储器寿命的缩短。虽然之前已经证明了超冷原子系统中的长寿命量子存储器，但到目前为止，这些只是实验室演示，并不具有商业可行性。这项可行性研究的目标是利用ColdQuanta的超冷原子技术构建使用激光冷却原子的光子量子存储器，在可商业扩展的平台上展示最先进的存储器寿命。在接下来的十年里，我们预计基于这些技术的设备将作为巨大的量子计算网络的关键组件得到广泛应用。

Quantum technologies have demonstrated the potential for vast technological improvements in communication, metrology, and computation. Although there are a variety of ways to leverage quantum technologies, photonic technologies -- those which are based upon encoding information in light -- are an exciting paradigm. Photons can be transmitted over complex free-space or fibre networks with minimal decoherence. This is due to their weak interaction with other fields or particles. Although this is a desirable feature, it also becomes a technical challenge as this leads to the requirement of probabilistic protocols for quantum information processing.Over recent decades, successive advances in laser science and atomic physics have made it possible to store and then retrieve, on demand, photonic information in an atomic vapour, therefore transitioning from probabilistic to deterministic protocols. This is named a photonic quantum memory. A substantial limiting factor in this technology is due to the motion of the atoms in which the photonic information is stored, leading to a reduction in memory lifetime. While long-lifetime quantum memories in ultracold-atom systems have previously been demonstrated, to date, these have only been laboratory demonstrations, and not commercially viable. The goal of this feasibility study is to leverage ColdQuanta's ultracold-atom technology to build a photonic quantum memory using laser-cooled atoms, showcasing state-of-the-art memory lifetime in a commercially scalable platform. In the coming decade, we anticipate devices built upon these techniques to become widespread as key components of vast quantum computing networks.