Q-Nav hits the press
The last week saw a flurry of press reports on 'quantum navigation' (Q-Nav) being about to replace GPS . .
The source was the 'Quantum Timing, Navigation and Sensing Showcase', held on 15 May at the National Physical Laboratory (NPL) to 'accelerate the exploitation of quantum mechanics for highly accurate timekeeping and advanced, GPS-independent navigation within the UK defence sector and wider industry'.
The Defence Science and Technology Laboratory (Dstl) presented a number of research projects, which included a table-top atom interferometer to provide 'ultra-precise, highly reliable positional data'.
Quantum mechanics already underpin the likes of semiconductors, microprocessors, MEMS devices and lasers. But this second 'quantum revolution' in the field of 'Timing, Navigation and Sensing' (TNS) is based around ultra-cold atoms cooled with lasers to temperatures a billion-times colder than outer space. At their lowest energies, the atoms become the coldest known bodies in the universe.
The Dstl prototype quantum accelerometer - resembling a 1-metre-long shoe box and containing 1 million cooled rubidium atoms - will be trialled on land in September 2015. It will operate along just one axis, before 2 more sets of lasers and trapped atoms are added to sense acceleration in 3 dimensions - representing the basis of a full inertial measurement unit (IMU).
Dstl's Neil Stansfield explains: 'Once we have understood the first generations, we'll start to miniaturise it for other applications'.
The focus of this activity is, literally, a quantum jump in accuracy. An example given is of a current submarine's inertial navigation system (INS), which might yield a 1 km error in 24 hrs; a Q-Nav device could typically give an error of only 1 metre over the same period.
But to yield this level of accuracy, a very accurate gravity map would be required. Edward Hinds, of the Centre for Cold Matter at Imperial College - developing the accelerometer for Dstl - explains: 'If the submarine passes an underwater mountain whose gravity attracts it to the west, that feels exactly like an acceleration to the east. This means that very good gravity maps will be required to navigate correctly.'
The Rt Hon David Willetts MP, Universities and Science Minister, comments:
'Among many promising areas, quantum technologies may bring game-changing advantages to future timing, sensing and navigation capabilities that could support multi-billion pound markets in the UK and globally.'
Details from NPL below . .