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Researchers at the University of Oxford connected two separate quantum processors using a special "photonic network interface," making them work together as one fully connected quantum computer.

This breakthrough could help solve complex problems that regular computers cannot handle. To be truly useful, quantum computers need to process millions of qubits (the basic unit of quantum information). However, fitting so many processors into one machine would make it extremely large.

The new approach links smaller quantum devices together, allowing them to share the work. In theory, this method can connect as many processors as needed.

While quantum teleportation has been done before, this study is the first to teleport "logical gates," which are the basic building blocks of quantum algorithms, across a network. This could lead to a future "quantum internet," where distant quantum processors form a super-secure network for communication and computing.

Lead researcher Dougal Main explained that, unlike previous teleportation experiments, their method allows separate quantum systems to interact. By carefully designing these interactions, they created logical quantum gates between qubits in different quantum computers, effectively linking them together as one system.

To test their method, the team ran Grover’s search algorithm, which can find items in large, unorganized datasets much faster than a regular computer. The success of this experiment shows how linking multiple quantum devices can lead to powerful, scalable quantum computers—potentially solving complex problems in hours that would take today's supercomputers years to complete.

Abstract
Distributed quantum computing (DQC) combines the computing power of multiple networked quantum processing modules, ideally enabling the execution of large quantum circuits without compromising performance or qubit connectivity1,2. Photonic networks are well suited as a versatile and reconfigurable interconnect layer for DQC; remote entanglement shared between matter qubits across the network enables all-to-all logical connectivity through quantum gate teleportation (QGT)3,4. For a scalable DQC architecture, the QGT implementation must be deterministic and repeatable; until now, no demonstration has satisfied these requirements. Here we experimentally demonstrate the distribution of quantum computations between two photonically interconnected trapped-ion modules. The modules, separated by about two metres, each contain dedicated network and circuit qubits. By using heralded remote entanglement between the network qubits, we deterministically teleport a controlled-Z (CZ) gate between two circuit qubits in separate modules, achieving 86% fidelity. We then execute Grover’s search algorithm5—to our knowledge, the first implementation of a distributed quantum algorithm comprising several non-local two-qubit gates—and measure a 71% success rate. Furthermore, we implement distributed iSWAP and SWAP circuits, compiled with two and three instances of QGT, respectively, demonstrating the ability to distribute arbitrary two-qubit operations6. As photons can be interfaced with a variety of systems, the versatile DQC architecture demonstrated here provides a viable pathway towards large-scale quantum computing for a range of physical platforms.