Laser Cooling of Strontium for Atom Interferometr

该项目旨在开发和优化用于物质波干涉测量的冷锶原子的高通量源。与目前使用铷的技术相比，锶具有许多优势，特别是锶原子具有非常长寿命的激发能级，从而产生极窄的跃迁（通常称为时钟跃迁）。像锶这样的二能级原子的原子结构也使它们对外部磁场的敏感度低于碱金属原子。这些特性使得冷原子锶源非常适合用于原子干涉仪等量子传感器。冷原子源的数值模拟，包括碰撞和激光吸收的影响，将进行改进目前的设计。将建立一个激光系统，通过光谱测量来表征光源。为了给原子干涉仪观测站和网络（AION）项目等大型仪器提供冷原子的通量，可能需要不止一代的原型。AION项目由基础物理量子技术项目资助，用于开发和建造下一代探测器，旨在探索引力波探测以及基本相互作用和暗物质探测。博士生和她的导师直接参与AION项目，冷原子源将根据其具体要求进行定制。与以前的工作相比，由于AION仪器本身就很大（第一代仪器高10米，将扩大到100米），因此在不考虑系统物理尺寸的情况下，强调获得锶费米同位素（Sr-87）的最高通量。这些不同约束条件下的优化需要新颖的设计。

This project aims to develop and optimise a high-flux source of cold strontium atoms for applications to matter-wave interferometry. Strontium has numerous advantages as compared to current technologies using rubidium in particular strontium atoms have excited energy levels with very long lifetimes that give rise to extremely narrow transitions (commonly called clock transitions). The atomic structure of two-level atoms like strontium also makes them less sensitive to external magnetic field than alkali-metal atoms. These properties make cold-atom strontium sources very suitable for quantum sensors such as atom interferometers. Numerical modelling of the cold-atom source, including the effects of collisions and absorption of the laser light, will be carried out to improve over current designs. A laser system will be set up to characterise the source by spectroscopy measurements. More than one generation of prototype may be necessary in order to provide the flux of cold atoms for large-scale instruments such as the Atom Interferometer Observatory and Network (AION) project. The AION project is funded under the Quantum Technology for Fundamental Physics programme to develop and construct a next-generation detector designed to explore gravitational wave detection alongside fundamental interactions and exploration of dark matter. The doctoral student, and her supervisor, are directly involved in the AION project and the cold-atom source will be tailored to its specific requirements. As compared to previous work there is a strong emphasis on obtaining the highest possible flux of the fermionic isotope of strontium (Sr-87) without regard to the physical size of the system since the AION instrument will itself be large (10m tall in the first generation and be scaled up to 100m). Optimisation with these different constraints will need to a novel design.