"Every electronic product needs a clock to keep it working and synchronised within the system and nowadays, across the world. Atomic clocks allow the highest possible precision in defining time, which is critical in determining position in navigation and defence systems, and in next generation telecommunications systems that power the internet age. Atomic clocks are presently bulky and expensive, and the world is demanding ever more timing accuracy. A main cost and size factor comes from the laser and optical systems used inside these next generation of clocks based on a lattice of strontium atoms. The miniaturisation of these systems and their cost reduction is now required to enable entry to a wider commercial market. This project develops special semiconductor laser light sources optimised to enable this miniaturisation and cost reduction. State of the art materials growth at CST Global and chip fabrication at the University of Glasgow is brought together alongside the UKs national measurement institute, NPL to solve these challenges."