Teleporting qubits scale quantum computer designs
Researchers at Oxford have shown a scalable and deterministic distributed quantum computing network for the first time that can be used for large quantum computer systems.
Distributed quantum computing (DQC) combines the computing power of multiple networked quantum processing modules, enabling the execution of large quantum circuits without compromising performance or qubit connectivity.
The team at the Cavendish Laboratory at the University of Oxford used a photonic quantum network to share the states of trapped ion qubits via quantum gate teleportation (QGT). This enables all-to-all logical connectivity to scale up a quantum system.
- Rigetti launches 84qubit Ankaa3 quantum computer
- Intel teams for Japanese quantum computer with hundreds of thousands of qubits
- First open source full stack ion trap quantum computer
- The tech behind quantum generative AI
For a scalable DQC architecture, the QGT implementation must be deterministic and repeatable; until now, no demonstration has satisfied these requirements, say the researchers in a paper in Nature.
In the demonstration, two photonically interconnected trapped-ion modules were two metres apart. These uses dedicated network qubits to deterministically teleport the state of a gate between the two circuit qubits in the separate modules with 86% fidelity.
The quantum circuits can be partitioned freely in this architecture, down to a minimum of one circuit qubit per module in the fully distributed case. Entanglement between the spatially separated qubits has been achieved experimentally in a variety of platforms, including diamond, superconducting qubits, neutral atoms and trapped ions. This highlights that the networking can be used with many different types of qubit at different temperatures.
The demo implemented distributed iSWAP and SWAP quantum circuits, compiled with two and three instances of QGT, respectively, demonstrating the ability to distribute arbitrary two-qubit operations between the modules.
The two qubit distributed system was then used as a quantum computer to execute an algorithm, Grover’s quantum search algorithm, with a 71% success rate. This is the first time this has been in system with non-local two-qubit gates.
The combination of the different qubit technologies with the entangled photonic network in the DQC architecture provides a viable pathway towards large-scale quantum computing for a range of physical platforms.
www.nature.com/articles/s41586-024-08404-x; www.oxford.ac.uk
If you enjoyed this article, you will like the following ones: don't miss them by subscribing to :
