You May Never Need To Charge Your Phone Again.

Researchers in Japan and China have made key findings toward the development of electronic devices that consume very little power.
Using new materials called ‘topological insulators,’ the team has identified a way to produce an electrical current at room temperature, without the need for external energy.

The work could lead to ultra-low power gadgets that never need charging.
The study revealed that non-magnetic element atoms in these materials act as the go-between for the magnetic interactions of other atoms, creating a system which doesn’t lose energy.

An electrical current can flow in this way due to the ferromagnetic properties — or the high susceptibility to magnetism — of the material.
Researchers first discovered this effect, in which an electrical current flows along an edge without losing energy, in the 1980’s, dubbing it the ‘quantum Hall effect.’
Until now, achieving this type of system required a very cold environment and a large external magnetic field.
This time around, researchers working primarily at SPring-8 in Japan tried to solve the problem by using ferromagnetic topological insulators, like ‘Cr-doped (Sb, Bi)2Te3.’


The material is neither a metal nor an insulator, according to Hiroshima University, but appears to have metallic properties on the surface or edges, while acting as an insulator on the inside.

A small film of it will generate an electric current only at the surface or edge.
Scientists were perplexed by this phenomenon, which occurs spontaneously at low temperatures, and does not result in energy loss.

It was first observed in 2007, and scientists did not know how it became so ferromagnetic.
To better understand why Cr-doped (Sb, Bi)2Te3 was so susceptible to magnetism, the researchers examined it first hand.

‘That’s why we selected the material as the object of our study,’ said Professor Kimura.