Scientists closer to unbreakable quantum data encryption

Unbreakable quantum data encryption networks that span thousands of kilometres are one step closer to reality, thanks to scientists from the ANU.

Researchers from the ANU Research School of Physics and Engineering and the University of Otago are developing a prototype quantum drive.

The team have managed to improve storage time by a factor of more than 100 on earlier prototypes, achieving a record six hours of storage time.

Quantum information has the potential to create unbreakable encryption because quantum particles can be created in a way that intrinsically links them, so that interactions with one entangled particle affects the other. But quantum states have traditionally proven difficult to harness.

“Quantum states are very fragile and normally collapse in milliseconds,” the RPSE's Manjin Zhong said.

“Our long storage times have the potential to revolutionise the transmission of quantum information... We believe it will soon be possible to distribute quantum information between any two points on the globe.”

The prototype method involves storing quantum information in the atoms of rare earth element europium embedded in a crystal.

Current prototype quantum networks use laser beams and span around 100km. The longer storage times of the prototype drive could pave the way for an alternative transmission method that would enable world-spanning networks.

“We can now imagine storing entangled light in separate crystals and then transporting them to different parts of the network thousands of kilometres apart,” Zong said. “So, we are thinking of our crystals as portable optical hard drives for quantum entanglement.”

Image courtesy of NASA Goddard Space Flight Center