Laser Cooling of Strontium for Atom Interferometr

该项目旨在开发和优化冷锶原子的高通量源，用于物质波干涉测量。与使用铷的当前技术相比，锶具有许多优点，特别是锶原子具有非常长的寿命的激发能级，这引起极窄的跃迁（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性低于碱金属原子。这些特性使得冷原子锶源非常适合于量子传感器，如原子干涉仪。将对冷原子源进行数值模拟，包括碰撞和激光吸收的影响，以改进目前的设计。将建立一个激光系统，通过光谱测量对光源进行测量。为了向原子干涉仪观测站和网络项目等大型仪器提供冷原子通量，可能需要一代以上的原型。AION项目由量子技术基础物理计划资助，旨在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索。博士生和她的导师直接参与了AION项目，冷原子源将根据其特定要求量身定制。与以前的工作相比，重点是获得锶（Sr-87）的费米同位素的最高可能通量，而不考虑系统的物理尺寸，因为AION仪器本身很大（第一代高10米，按比例放大到100米）。优化这些不同的约束将需要一个新颖的设计。

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.