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Weird electrons may shrink your laptop

A new type of material with bizarre acting electrons could bring dramatic advances in the world of electronics, predicts an Australian researcher.

Because of the way its electrons spin, the material could be used for applications where information needs to be densely packed, says Associate Professor Xiaolin Wang from the University of Wollongong.

If his work is confirmed, this could mean slimmer laptops and mp3 players.

"Conventional electronics and devices use only the electron's charge for information processing. When both spin and charge are used simultaneously, astonishing and unusual physical phenomena occur," he says.

Wang's theoretical research is published in the journal Physical Review Letters.

The new material is a "spin gapless semiconductor", Wang says.

"[It's] completely different to other materials found in nature, which are generally called insulators, semiconductors and metals."

The key to the difference lies in the properties of the electrons, tiny, negatively charged particles found within the new material, he says.

When an electric current is applied to a normal material like a standard metal or semiconductor, its electrons move in the opposite direction to the electric current.

As they do so, they also spin on their own axis, a bit like when a tennis ball spins as it is hit.

Under normal circumstances, half the electrons in a material spin in one direction and half in the other.

But in the new material, all the electrons are thought to spin in the same direction.

"This is the special feature of this material," Wang says. "All the electrons move forward with the spin pointing in the same direction."

In the tennis analogy, it is as if all the balls have been hit with top-spin.

Based on theoretical calculations, Wang has shown that a type of lead-platinum-oxide compound will have these properties.

The researchers have already discovered a special property of this material that relates to the spin of the electrons. They are working on a paper describing that work.

Crucially, Wang has also shown that theoretically it would be a simple matter to manipulate the number of electrons and direction of their spin in this new material.

"We can change the spin direction by changing the external conditions such as temperature or electric current," he says.