A team of researchers from the University of the Witwatersrand in Johannesburg, South Africa, have demonstrated a new and a record-setting quantum protocol for sharing a secret amongst many parties.
This quantum protocols used an 11 dimension quantum state to share a secret among 10 parties. A higher dimension of the state means a big secret can be shared and can be shared with more number of parties. This protocol is a record in the dimension of the state and the number of parties.
The benefit of a quantum network is that the secret can be unlocked only if the parties trust each other eliminating eavesdrop
“In traditional secure quantum communication, information is sent securely from one party to another, often named Alice and Bob. In the language of networks, this would be considered peer-to-peer communication and by definition has only the two nodes: sender and receiver,” says lead author Professor Andrew Forbes from the School of Physics at Wits University
We all know that most of the times there needs to be one sender and several receiving parties which is not allowed by traditional quantum communications like Quantum Key Distribution (QKD) as it only supports one to one transfer.
The team used structured light (means ”Patterns of light”) as quantum photon states to distribute information from one sender to 10 parties. Then they used some nifty quantum tricks to engineer the protocol in a way that only if the parties trust one another, the secret is revealed. The level of trust can be set from just a few of the parties to all of them.
“Our work pushes the state-of-the-art and brings quantum communication closer to true network implementation,” says Forbes. “When you think of networks you think of many connections, many parties, who wish to share information and not just two. Now we know how to do this the quantum way.”
Journal Reference:
Jonathan Pinnell, Isaac Nape, Michael Oliveira, Najmeh TabeBordbar, Andrew Forbes. Experimental Demonstration of 11‐Dimensional 10‐Party Quantum Secret Sharing. Laser & Photonics Reviews, 2020; 2000012 DOI: 10.1002/lpor.202000012
