Taking a significant step toward realizing the potential of quantum computing, researchers at the University of Oxford have unveiled a groundbreaking advancement in distributed quantum computing.
The scientists linked two separate quantum processors that were just six and a half feet apart, using a photonic network interface. This demonstrated how separate quantum computers can collaborate over distance, a feat that could revolutionize the future of computing. This work is a crucial step toward the creation of a scalable quantum computer.
The breakthrough, detailed in a paper published in the journal Nature, tackles one of quantum computing’s most persistent challenges: scalability. Until now, the vision of powerful, large-scale quantum supercomputers seemed distant, constrained by the need to keep massive numbers of qubits in a single machine. This new approach, however, shows that by connecting smaller quantum devices, computations can be distributed across a network. As Main put it, “This work could eventually lead to a quantum internet of ultra-secure processors.”
While quantum teleportation of states has been demonstrated before, this study marks the first time logical gates—the fundamental building blocks of algorithms—have been teleported across a network link. The researchers believe this achievement could pave the way for a future ‘quantum internet,’ where remote processors could form an ultra-secure network for communication, computation, and sensing.
While quantum teleportation is not new in theory, the Oxford team’s success marks a significant leap from lab experiments to a practical application. Previous studies have shown that quantum bits, or qubits, can be transferred across physically separated systems. However, the real-world application of these findings, especially in terms of scalability and secure communication, has long remained elusive. The researchers’ work provides a glimpse into how quantum computing could soon break past those barriers.
“In our study, we use quantum teleportation to create interactions between these distant systems,” said Dougal Main, from the Department of Physics at the University of Oxford, who led the study. “By carefully tailoring these interactions, we can perform logical quantum gates – the fundamental operations of quantum computing – between qubits housed in separate quantum computers. This breakthrough enables us to effectively ‘wire together’ distinct quantum processors into a single, fully-connected quantum computer.”
The team demonstrated the potential of this distributed quantum computing method by executing Grover’s search algorithm, which allows for faster searching in large datasets by exploiting quantum phenomena like superposition and entanglement.
This experiment not only shows that networked quantum computing is feasible with current technology, but also highlights how such a system could eventually lead to quantum computers that outperform traditional supercomputers. This breakthrough sets the stage for scalable, high-performance quantum computers that could solve complex problems in hours, a task that would take current supercomputers years.
“Our experiment demonstrates that network-distributed quantum information processing is feasible with current technology. Scaling up quantum computers remains a formidable technical challenge that will likely require new physics insights as well as intensive engineering effort over the coming years,” Professor David Lucas, principal investigator of the research team and lead scientist for the UK Quantum Computing and Simulation Hub, led from the Department of Physics, said.
The research was funded by UK Research and Innovation (UKRI) through the Engineering and Physical Sciences Research Council (EPSRC), as part of the UK Quantum Computing and Simulation (QCS) Hub within the National Quantum Technologies Program.
What is quantum computing?
Think of a traditional computer as a person solving a maze by trying one puzzle piece at a time. This way can take a long time to find the right solution. A quantum computer, on the other hand, is like a magical puzzle solver. Because it can explore many possibilities simultaneously, it can solve the maze much faster. This special ability comes from two quantum tricks: superposition, where the computer can look at multiple solutions at the same time, and entanglement, where different parts of the computer are linked and can work together more efficiently. So, quantum computers can solve certain problems way quicker than regular computers.
Quantum computing is an emergent field of cutting-edge computer science that uses the principles of quantum mechanics to solve problems too complex for classical computers and solve them much faster than conventional computers. Instead of using traditional bits (zeroes and ones) to represent data, quantum computers use quantum bits or qubits. While still in its early stages, quantum computing has the potential to revolutionize fields such as cryptography, drug discovery, and materials science.
Quantum entanglement is when two particles, such as a pair of photons, remain correlated even when separated by vast distances. This allows them to share information without having to travel physically.
Quantum teleportation is the process of transferring quantum information over long distances almost instantly, using entanglement.