Researchers from the University of the Witwatersrand and ICFO – The Institute of Photonic Sciences have demonstrated a method of transporting images across a network without physically sending the image, using a teleportation-inspired configuration. This quantum transport of high-dimensional information is a significant step towards a quantum network for high-dimensional entangled states. The team used a nonlinear optical detector, achieving a new state-of-the-art of 15 dimensions. The technology could have practical applications in secure banking, with information appearing to be ‘teleported’ from sender to receiver. The research was led by Professor Andrew Forbes and Dr Bereneice Sephton.
Quantum Teleportation of Images Using Light
Researchers from the University of the Witwatersrand, Johannesburg, and ICFO – The Institute of Photonic Sciences, Spain, have demonstrated a method of transporting images across a network without physically sending the image. This is achieved through a teleportation-inspired configuration, marking a significant step towards the realization of a quantum network for high-dimensional entangled states.
Quantum Communication and Information Security
Quantum communication over long distances is crucial to information security. It has been demonstrated with two-dimensional states (qubits) over very long distances between satellites. Quantum optics allows for an increase in the alphabet and to securely describe more complex systems in a single shot, such as a unique fingerprint or a face. This new method of communication does not require the physical sending of information from one party to another.
The Role of Professor Andrew Forbes and His Team
Professor Andrew Forbes, the lead PI from Wits University, explains that teleportation of information is now possible so that it never physically travels across the connection. However, teleportation has so far only been demonstrated with three-dimensional states, requiring additional entangled photons to reach higher dimensions. In this research, the team performed the first experimental demonstration of the quantum transport of high-dimensional states with just two entangled photons as a quantum resource.
The Use of Nonlinear Optical Detector
The team used a nonlinear optical detector that circumvents the need for additional photons, yet works for any “pattern” that needs to be sent. They report a new state-of-the-art of 15 dimensions, with the scheme scalable to even higher dimensions. This paves the way for quantum network connections with high information capacity.
Practical Applications in Banking
The potential of this new quantum transport protocol is illustrated in a banking setting. A customer wishing to send sensitive information to a bank, such as a fingerprint, would traditionally have to physically send the information, always with the risk of interception. In the newly proposed quantum transport scheme, the bank sends a single photon (one of an entangled pair) with no information to the customer, who overlaps it on a nonlinear detector with the information that is to be sent. As a result, the information appears at the bank exactly as if it had been teleported there.
Future Developments and Challenges
Dr Adam Vallés from ICFO, one of the leads on the project, hopes that this experiment motivates further advances in the nonlinear optics community. However, he cautions that the current configuration could not prevent a cheating sender from keeping better copies of the information to be teleported. Despite this, the configuration can already be used to establish a high-dimensional secure channel for quantum communications between two parties.
The team acknowledges the significant contribution of Dr Bereneice Sephton from Wits University, who performed the key experiments. The team plans to continue working in this direction, with the next step focusing on quantum transport across an optical fibre network.
“Traditionally, two communicating parties physically send the information from one to the other, even in the quantum realm,” says Professor Andrew Forbes, the lead PI from Wits University. “Now, it is possible to teleport information so that it never physically travels across the connection – a “Star Trek” technology made real.”
“This protocol has all the hallmarks of teleportation except for one essential ingredient: it requires a bright laser beam to make the nonlinear detector efficient, so that the sender could know what is to be sent, but doesn’t need to know,” explains Forbes. “In this sense, it is not strictly teleportation, but could be in the future if the nonlinear detector could be made more efficient.”
“We hope that this experiment showing the feasibility of the process motivates further advances in the nonlinear optics community through pushing the limits towards a full quantum implementation,” says Dr Adam Vallés from ICFO (Barcelona), one of the leads on the project who worked on the experiment during his postdoctoral fellowship at Wits University.
“We have to be cautious now, as this configuration could not prevent a cheating sender from keeping better copies of the information to be teleported, which means we could end up with many Mr Spock clones in the Star Trek world if that is what Scotty wanted.
Vallés adds: “Performing such proof-of-concept experiments with currently available technology has been an interesting journey, and we have Dr Bereneice Sephton from Wits to thank for her determination and the comprehensive skills set needed to tame such an experimental beast. This is a true laboratory endeavour for which she should be lauded.”
Forbes echoes the sentiment: “This was an heroic experiment and Dr Bereneice Sephton must be recognised as she is the one who got the system to work and performed the key experiments.”
Summary
Researchers have demonstrated a method of ‘teleporting’ images across a network using light, without physically sending the image, marking a significant step towards a quantum network for high-dimensional entangled states. This technology could potentially increase information security in applications such as banking, where sensitive data could be sent without the risk of interception, as no information is physically sent between the two parties.
- Researchers from the University of the Witwatersrand, Johannesburg, and ICFO – The Institute of Photonic Sciences, Spain, have demonstrated a method of transporting images across a network without physically sending the image.
- The team used a teleportation-inspired configuration, which is a significant step towards realising a quantum network for high-dimensional entangled states.
- Quantum communication over long distances is crucial for information security and has been demonstrated with two-dimensional states over very long distances between satellites.
- The research team performed the first experimental demonstration of the quantum transport of high-dimensional states with just two entangled photons, resulting in the information appearing to be “teleported” from the sender to the receiver.
- The team used a nonlinear optical detector that circumvents the need for additional photons, yet works for any “pattern” that needs to be sent.
- The researchers achieved a new state-of-the-art of 15 dimensions, with the scheme scalable to even higher dimensions.
- The potential applications of this new quantum transport protocol include secure banking transactions.
- The research was led by Professor Andrew Forbes from Wits University and Dr Adam Vallés from ICFO, with key experimental work performed by Dr Bereneice Sephton from Wits University.

