Device just one-atom thick a quantum leap in technology

It is only a tiny device - a pancake-like layer of 300 atoms hovering in space.

Yet it has the potential to provide insights into how materials behave at the quantum level that none of today's conventional computers would be capable of calculating.

When fully operational, its performance could only be matched by an impossibly large machine, according to Michael Biercuk, a Sydney physicist and member of the international team that built and tested it.

''The system we have developed has the potential to perform calculations that would require a supercomputer larger than the size of the known universe. And it does it all in a diameter of less than a millimetre,'' Dr Biercuk, of the University of Sydney, said.

The device, known as a quantum simulator, is just one-atom thick.

Its 300 charged beryllium atoms are trapped in suspension by magnetic and electric fields, and their interactions can be controlled by lasers.


Dr Biercuk said the tiny device's role was akin to that of a scale model of an aircraft wing, which engineers might test in a wind tunnel to try and design a better plane.

''Tremendous insights about complex quantum systems can be gleaned using a quantum scale model,'' he said. For example, scientists want to design new materials, like high-temperature superconductors, whose properties depend on the collective quantum behaviour of billions of atoms.

The traditional approach to design would be to run computer models that mimic how all the particles in a material interact to try and predict its overall properties. But this is extremely difficult with quantum systems, because particles can behave weirdly at the quantum level, such as being in two distinct states at the same time - a characteristic known as superposition. ''Beyond about 30 to 40 particles interacting there is no computer in the world that can simultaneously represent all the different possibilities of how those particles interact,'' Dr Biercuk said.

Built by a team led by Joseph Britton, of the US National Institute of Standards and Technology, the device has broken the record for the number of interacting elements in a programmable quantum simulator.

The results are published in the journal Nature.

Dr Biercuk said that understanding the physics underlying high-temperature superconductivity could revolutionise power distribution and high speed transport.