Quantum control and entanglement of 6+ spin qubits in diamond

The nitrogen vacancy (NV) centre in diamond is a promising candidate for quantum networks. NVs can be entangled remotely [1], and coupling to ¹³C nuclear spins in the environment provides qubits for the storage and processing of quantum information [2]. In recent years, basic building blocks for a quantum network have been demonstrated, including quantum error correction [2] and entanglement distillation [3]. A key challenge is to realise high-quality control over multiple ¹³C spin qubits.

In this talk, I will show how a novel two-qubit gate - based upon radio frequency driving interleaved with dynamical decoupling - enables quantum entanglement of 6+ spins. The results are the largest entangled state realised on this platform, and are a key step for error correction and larger quantum networks with NV centres.

[1] B. Hensen et al. Nature 526.7575 (2015)
[2] J. Cramer et al. Nature communications 7(2016)
[3] N. Kalb et al. Science 356.6341 (2017)