Gold Chip Ion-Trap Image Captures Top Prize

An image of a gold chip used to trap ions for use in quantum computing has won the overall prize in a national science photography competition, organised by EPSRC.

‘Microwave ion-trap chip for quantum computation’, by Diana Prado Lopes Aude Craik and Norbert Linke, from the University of Oxford, shows the chip’s gold wire-bonds connected to electrodes which transmit electric fields to trap single atomic ions a mere 100 microns above the device’s surface.

The image, taken through a microscope in one of the university's cleanrooms, came first in the Eureka category as well as winning overall against many other stunning pictures, featuring research in action, in the EPSRC competition – now in its third year.

Doctoral student Diana Prado Lopes Aude Craik, explained how the chip works: “When electric potentials are applied to the chip’s gold electrodes, single atomic ions can be trapped. These ions are used as quantum bits (‘qubits’), units which store and process information in a quantum computer. Two energy states of the ions act as the ‘0’ and ‘1’ states of these qubits. Slotted electrodes on the chip deliver microwave radiation to the ions, allowing us to manipulate the stored quantum information by exciting transitions between the ‘0’ and ‘1’ energy states.

“This device was micro-fabricated using photolithography, a technique similar to photographic film development. Gold wire-bonds connect the electrodes to pads around the device through which signals can be applied. You can see the wire-bonding needle in the top-left corner of the image. The Oxford team recently achieved the world’s highest-performing qubits and quantum logic operations.”

The development of the ion-trap chip was funded jointly by the EPSRC and the US Army Research Office.