Scientists from the University of Bristol’s Centre for Quantum Photonics have announced that they have developed a working silicon chip that will allow the mass manufacture of microscopic quantum chips in the near future.
Quantum computing would allow for the computation of complex tasks at speeds beyond even the capabilities of the latest supercomputers, such as stock market analysis, simulation of scientific lab conditions (or space) and potentially even artificial intelligence.
"It had previously been thought that a large-scale quantum computer will not become a reality for at least another 25 years," said Jeremy O’Brien, director of the Centre for Quantum Photonics.
"However, we believe that, using our new technology, a such a device, in less than 10 years, be performing important calculations that are outside the capabilities of conventional computers."
Unlike conventional bits or transistors, which can exist in one of only two states at any one time (1 or 0), a quantum computing qubit can be in several states at the same time. This means it can process a much larger amount of information at a much greater rate, and on a microscopic scale.
Quantum processing chip – full chip size is 2mm x 4mm. The processing part in the centre is just 100um by 400um and contains over 200 components.
Scientists have been working on quantum computing for decades as the next phase of evolution in computing. Until now, it had been considered a sci-fi dream that wouldn’t see the light of day for decades – and mainstream usage decades after that.
The University of Bristol team claims that it has solved much of the problems by moving from using glass-based circuits to silicon-based circuits.
This is the same material routinely used en masse to build the tiny electrical processors in all computers and smart phones. However, unlike conventional silicon chips that work by controlling electrical current, these circuits manipulate single particles of light (photons) to perform calculations.
The circuits exploit strange quantum mechanical effects such as superposition (the ability for a particle to be in two places at once) and entanglement (strong correlations between particles that would be nonsensical in our everyday world).
This means the new chips use the same manufacturing techniques as conventional microelectronics, and can be scaled for mass-manufacture.
"Using silicon to manipulate light, we have made circuits over 1000 times smaller and more complex than current glass-based technologies. For the first time, we can mass-produce this kind of chip, and the much smaller size means it can be incorporated in to technology and devices that would not previously have been compatible with glass chips" says Mark Thompson, deputy director of the Centre for Quantum Photonics.
"This is very much the start of a new field of quantum-engineering, where state-of-the-art micro-chip manufacturing techniques are used to develop new quantum technologies and will eventually realise quantum computers that will help us understand the most complex scientific problems."
In the short term, the team plans to implement quantum-secure communications chips that could work in mobile phones and laptop computers – increasing the security of online banking and internet shopping. The aforementioned nature of quantum mechanics makes encryption more compex, and the Bristol team claims this would make smartphones essentially ‘un-hackable’.
In the long term the researchers believe that their device represents a new route to the long dreamed of quantum computer. These devices will have unprecedented computational power for tasks including search engines and the design of new materials, pharmaceuticals and clean energy devices.
"Our approach will ultimately allow us to achieve component densities millions of times greater than current technologies, enabling miniature quantum circuits that could potentially fit inside a mobile phone, for example to enable quantum-secure communications for internet banking", said Thompson.
The team’s research will be unveiled at the British Science Festival this week.
