Three-dimensional Fourier Imaging of Thousands of Individual Solid-State Quantum Bits – A Tool for Spin-Based Quantum Technology


 Nitrogen vacancies in diamond (NVs) are frequently considered possible candidates to constitute the building blocks of spin-based quantum computers. The main caveats to this approach are the lack of a reliable process to accurately place many NVs in close proximity to each other (~10–20 nm) to enable an adequate spin-spin interaction; and the inability to read out and selectively manipulate the quantum states of many such closely spaced NVs. A possible approach to overcome these issues includes the following: (i) making use of a diamond dense with NVs in random ("as-produced") 3D positions; (ii) mapping out their individual locations at high spatial resolution (in 3D); (iii) employing techniques for selective spin manipulation based on the mapped 3D locations of the NVs; and (iv) making use of imaging techniques to read out the quantum state of the NVs. Within this grand vision, we present here a tool that can support this scheme—namely, an approach to the efficient high accuracy 3D mapping of many thousands of individual NVs in a diamond via magnetic resonance imaging (MRI). In the present work, the NVs’ spacings and the corresponding imaging resolution are in the submicron-scale, but the same approach can be scaled down to support a resolution lower than 10 nm in diamonds with dense NVs, as is required for practical quantum computing applications.