Distributed quantum computation with spins in diamond

A potential path towards large-scale quantum processors is to distribute computations over a quantum network [1]. By connecting many small modules through interconnects one can sidestep the challenge of placing dense arrays of qubits on a single chip of ever-increasing complexity. Optically active spin qubits in diamond are a promising platform for such distributed quantum computations and simualtions, as they combine long-lived qubits at high operating temperatures with a coherent interaction with photons that enables optical interconnects [2]. Ultimately, moving to large-scale systems will require using error-corrected logical qubits that are operated fault tolerantly, so that reliable computation becomes possible despite noisy operations.



In this talk, I will present our progress towards realizing distributed error correction and computation with diamond spin qubits within the Fujitsu – QuTech collaboration. In particular, I will discuss our recent results that demonstrate a fault-tolerantly operated logical qubit based on the five-qubit code using flag qubits [3]. Additionally, I will discuss the main challenges towards distributed quantum error correction, and ultimately larger-scale quantum computations, based on spins in diamond or similar materials.



[1] Nickerson et al., Phys. Rev. X 4, 041041 (2014)

[2] Pompili et al., Science 372, 259 (2021)

[3] Abobeih et al., Nature 606, 884 (2022)