Fibre optic cables use pulses of light to transmit information, but currently information can only be stored through the colour of the light, and whether the wave is horizontal or vertical.
By twisting light into a spiral, engineers effectively create a third dimension for light to carry information: the level of orbital angular momentum, or spin. “It’s like DNA, if you look at the double helix spiral,” said Min Gu from RMIT University. “The more you can use angular momentum the more information you can carry.”
Researchers in the US had previously created a fibre that could twist light, but Gu’s team is the first to create a reasonable-size detector that can read the information it holds.
Previous detectors were “the size of a dining table”, but the new detector is the width of a human hair. “We could produce the first chip that could detect this twisting and display it for mobile application,” Gu said.
The technology could be used to upgrade fibre optic networks like Australia’s national broadband network
Gu said his new research could still work with networks with large amounts of copper wire.
“We will definitely reduce this hurdle,” he said. “We will make this transfer more efficient.”
However, because the new cables are required to effectively twist light, any upgrade could involve replacing existing fibre networks.
Sounds exciting but years away from being implemented.