UK claims lead in quantum sensor development

May 16, 2014 // By Nick Flaherty
The UK believes it has a major global lead in the development of quantum clocks and sensors for navigation.

The quantum research is delivering stability and accuracy four orders of magnitude better than other systems, says Stephen Timms, fellow at the UK DSTL which is part of the Ministry of Defence. This will allow tradeoffs for smaller, chip scale devices, he says and more accurate control of systems.

Researchers have already been able to build wafer level quantum sensors that assemble a cloud of ions, confine them and cool them down with a semiconductor laser and diffraction gratings so that the quantum states become entangled. Tiny changes in acceleration can be detected by the entangled ions, providing an accelerometer or a gravity detector. A team at the UK's national Physical Laboratory (NPL) are using a standard semiconductor micromachined (MEMS) process to build the channels and cantilevers with gold electrodes that confine the ion cloud on a series of chips, on a four inch wafer with the required consistency. MEMS lends itself to building these kinds of sensors as the heating effect of the RF signals used to measure the state of the ions is significantly reduced.

A recent (May 2014) gathering of researchers at NPL saw predictions of a commercial chipscale 1D quantum accelerator in the next three years, with a 3D sensor within five years. New technologies for ultra high vacuum(UHV) packaging are being developed along with investigating the use of graphene for more less noisy electrodes.

Other researchers at the University of Southampton are developing an ion trap on chip with UHV, using packaging materials such as aluminosilicate 'gorilla’ glass that is also used for phone and tablet screens.

Researchers at NPL are also using hollow fibres filled with caesium atoms to create miniature atomic clocks. These can provide high accuracy for navigation systems in small, light packages.

A team at consultancy Plextek in Cambridge is working on a scheme to use more accurate timing for groups of unmanned underwater vehicles. By exchanging estimates of position and