Quantum sensing will also help in monitoring volcanoes.
Glasgow University researchers are working with Italian volcanologists to place a network of 40 tiny gravimeters on Sicily’s Mount Etna, one of the most active volcanoes in the world. As magma chambers fill up below ground their gravity readings will change, thus giving advanced warning of volcanic activity.
Scientists already use an array of instruments – such as seismometers, ground deformation recorders, gas monitors, infrared cameras and satellite imagers – to monitor volcanoes.
But a network of cheap and permanent gravimeters is a potential game changer, giving far more accurate readings of magma movements.
“Essentially, we will for the first time be able to provide gravity imaging for long time periods,” says Prof Giles Hammond at Glasgow’s Institute of Gravitational Research.
Using the current generation of bulky non-quantum gravimeters means scientists have to go on to the mountain and move them around – which has risks on an active volcano like Etna.
The team is using micro- and nano-fabrication techniques to make tiny quantum gravimeters on silicon wafers that are 10 times cheaper than conventional models.
“Our sensor is a mass on a soft spring, and where that spring sits with a given mass is dependent on gravity. As gravity changes, where that spring sits also changes,” explains Prof Hammond.
The university is also working on a special 3D type of lidar that will enable you to look round corners, or “see” into a room.
Conventional lidar measures the distance to an object by illuminating it with pulsed laser light and then measuring the reflected pulses. But quantum technology enables scientists to measure the arrival time of single photons with very high accuracy, in trillionths of a second.
“In a canyon you’ll hear your voice echo back,” says Prof Daniele Faccio, head of Glasgow University’s Extreme Light group.
“You can do the same with light or a laser beam. The light will bounce off walls – so long as you have the geometry right. Then you can build a 3D image using this data.”
The aim is to develop next-generation lidar for self-driving cars to give them enhanced awareness – through fog, smoke and over longer distances.
Glasgow’s prototype sensor can already detect moving people 100m away, even when they’re a few metres round a corner.