Laser Cooling of Strontium for Atom Interferometr

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.