Portable atomic clocks could reduce reliance on satellite navigation

Timekeeping has been vital to navigation for centuries. The Royal Observatory at Greenwich proudly displays the chronometers designed and built by John Harrison in the 18th century that allowed longitude to be determined by ships at sea, with the result that the zero meridian runs through London. Today, the hyper-accurate clocks that allow us navigate are mainly housed on satellites, such as the American-owned global positioning system (GPS) and the European Union’s Galileo consolation, the subject of some controversy in the UK owing to legal aspects of Brexit.

A team at the emerging photonics laboratory (EPic Lab) at Sussex University is working on technology to make super accurate clocks portable: something that would free users from the dependants on GPS or Galileo for navigation. This would reduce their exposure to the whims of international politics, while also allowing them to navigate where there is no satellite signal.

Their breakthrough is in improving the accuracy of the lancet – the device in the clock responsible for counting, analogous to the pendulum in a traditional mechanical clock – by 80 per cent, outperforming other teams around the world working on similar projects.