Researchers in the Netherlands have shown that they can transmit quantum information via an intermediate node, a feature needed to enable the so-called quantum Internet.
In recent years, scientists have argued that the quantum Internet is a more desirable network for transmitting secure data, in addition to being necessary when connecting multiple quantum systems. All this has attracted investment from the US governmentamong others.
Despite the promise, the essential elements for the creation of a functional quantum internet are still missing.
Transmitting quantum information — the superposition of states — between two nodes becomes possible through the process of entanglement that occurs when scientists create two or more particles such that the quantum state of each particle cannot be described independently of the state of the others. In this way, researchers have shown that they can “teleport” quantum information between two nodes.
Researchers at Qutech, a quantum computing research institute founded in 2014 by Delft University of Technology and the Dutch Organization for Applied Scientific Research, have now demonstrated that they can create the impact via an intermediate node, a necessary condition for a functioning computer network.
As a learning aid in the otherwise hard-to-decipher field, PhD student Sophie Hermans and her colleagues named the web nodes with nicknames related to the information sections between us: Alice, Bob, and Charlie. Alice and Charlie have no direct connection between them.
The researchers’ demo first creates implicit quantum states between the neighboring nodes: Alice and Bob. The second node, or processor, then stores its involved state. Next, Bob creates an involved state with Charlie. Quantum scientists then exploited a known effect in their field. By measuring Bob’s condition, they influence the involvement, creating a direct bond between Alice and Charlie.
The team later coded the “message” information on an extra kbit, which when measured along with Charlie’s involved condition, teleports the information to Alice, according to article published in Nature this week.
While a significant demonstration of work concepts that may well become relevant in quantum networks, as with much in the quantum computing field, practical applications are a bit far-fetched.
In an accompanying article, Oliver Slattery, a doctor of physics at the Information Technology Laboratory, National Institute of Standards and Technology in Maryland, and Yong-Su Kim, a senior researcher at the Center for Quantum Information, Korea Institute of Science and Technology, said constant teleportation of information about a quantum network has been left behind.
“Hermans et al [have] managed to teleport quantum information between Alice and Charlie – two nodes without a direct link. This achievement is not only a gain for fundamental science but also represents a breakthrough in the real-world problem solving necessary to move this fascinating quantum application to the next step.
“Reliable teleportation around a quantum network is a long way off, and this work highlights the massive challenge ahead for the true realization of the quantum internet – but Hermans et al. Offers a possible way forward. even higher interlocking rates, and an improved optical interface will increase the efficiency with which remote nodes are involved, ”they said.
Three network nodes, Alice (A), Bob (B) and Charlie (C), are connected by fiber optic connections (lines) in a line configuration. Each arrangement has a communicating qubit (purple) that allows interlacing with its neighboring node.
However, the promise to move quantum data around a network securely has such power that the U.S. government is determined not to be left behind.
In 2020, the U.S. Department of Energy laid out a “draft strategy” for developing a national quantum Internet.
Energy Secretary Dan Brouillette said: “By building this new and emerging technology, the United States continues its commitment to maintaining and expanding our quantum capabilities.”
La The then government statement said the quantum internet “could become a secure communication network and have a profound impact on areas critical to science, industry and national security.” ®