(PhysicsWorld) Imperfections in diamond enable a 10-qubit register – a collection of qubits that can store data in a quantum computer – report researchers at Delft University of Technology in the Netherlands and Element Six in the UK. Their diamond-based system is capable of preserving an arbitrary single-qubit state for over a minute – a record for a solid-state qubit. The multiqubit register signifies important progress in quantum-information processing, which requires a large number of qubits.
PhD-researcher Conor Bradley at QuTech and the Kavli Institute of Nanoscience, both in Delft University of Technology, alongside his collaborators, based their qubits on a defect in diamond consisting of a nitrogen atom and an adjacent empty lattice site in place of two carbon atoms – a nitrogen-vacancy (NV) centre. The 10 qubits in their quantum register are the electron and nitrogen nuclear spins of the NV center, along with eight surrounding carbon-13 nuclear spins. Researchers then show that the register is fully connected by preparing entangled states for all 45 possible qubit pairs.
The study supervisor, Tim Taminiau, expects that the new method will be applied in other spin configurations in diamond, silicon and silicon carbide. He remarks: “Our findings pave the way for advanced quantum algorithms, quantum error correction and large multi-qubit quantum networks based on tens of solid-state spin qubits.”