Scientists create atom transistor to speed up computers

Melbourne, Dec 10 (ANI): An international team of scientists has created a tiny transistor that could one day help quantum computers process impossibly large amounts of information.

The researchers are the first to make a transistor's electrical current pass through a single atom in a controllable way, another step towards the quantum computer chip.

One of the research leaders, Professor Andrew Dzurak of the University of New South Wales, revealed that although still a couple of decades away, quantum computers have the potential to solve calculations faster than all current computers working at once.

"They could revolutionise society by doing things like developing more accurate climate change models and predicting how people will respond to new medicines without the need for lengthy trials," ABC Science quoted him as saying.

But in order to create these computers, researchers first need to develop quantum units of information called 'qubits' - and this can only be done with single-atom transistors.

The research team, involving scientists from the University of Melbourne, the University of New South Wales and Helinski University of Technology in Finland, are the first to successfully create these tiny devices on a silicon computer chip.

According to Dzurak, scientists have struggled to create single-atom transistors until now because it's extremely difficult to control the placement of atoms at such a small scale.

"Transistors work almost like a sink - electrons pass like water from a source electrode to a drain electrode - and there's a gate that turns the flow on and off," he said.

By placing the single atom close enough to the source and drain, the team made electrons pass through it in a controllable way using a phenomenon known as quantum mechanical tunnelling.

Dzurak said the main benefit of these single-atom transistors isn't their sizes, which are not much smaller than regular transistors due to the bulk of electrodes. Instead it is the way they store information.

Instead of just being encoded with a one or a zero, as in traditional binary code, single-atom transistors can also exist in various superpositions that allow them to store exponentially more data than current transistors.

Dr Andrea Morello, a University of New South Wales' researcher also involved in the project, said the next step is to learn how to accurately measure which way the electrons are spinning around the single-atoms in the transistors - something the team is quite close to achieving.

This will eventually allow the researchers to control the direction of spin and code information into the transistors.

"After that, the hard part will be to make two transistors talk to each other, but once you've demonstrated it can work, it shouldn't be too hard to produce these devices on a large scale," Morello added.

Their research is published online in the journal Nano Letters. (ANI)