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arXiv · 1810.03253

Scalable nuclear-spin entanglement mediated by a mechanical oscillator

Puhao Cao·Ralf Betzholz·Jianming Cai
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Abstract

We propose a solid-state hybrid platform based on an array of implanted nitrogen-vacancy (NV) centers in diamond magnetically coupled to a mechanical oscillator. The mechanical oscillator and the NV electronic spins both act as a quantum bus and allow us to induce an effective long-range interaction between distant nuclear spins, relaxing the requirements on their spatial distance. The coherent nuclear spin-spin interaction, having the form of an Ising model, can be maintained in the presence of mechanical damping and spin dephasing via a pulsed dynamical decoupling of the nuclear spins in addition to the microwave driving field of the electronic spins. The present hybrid platform provides a scalable way to prepare multipartite entanglement among nuclear spins with long coherence times and can be applied to generate graph states that may be used for universal quantum computing.

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Puhao Cao, Ralf Betzholz, Jianming Cai. 2018-10-08. Scalable nuclear-spin entanglement mediated by a mechanical oscillator. https://doi.org/10.1103/physrevb.98.165404

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