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arXiv · 1712.08857

High precision single qubit tuning via thermo-magnetic field control

David A. Broadway·Scott E. Lillie·Nikolai Dontschuk·Alastair Stacey·Liam T. Hall·Jean-Philippe Tetienne·Lloyd C. L. Hollenberg
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Abstract

Precise control of the resonant frequency of a spin qubit is of fundamental importance to quantum sensing protocols. We demonstrate a control technique on a single nitrogen-vacancy (NV) centre in diamond where the applied magnetic field is modified by fine-tuning a permanent magnet's magnetisation via temperature control. Through this control mechanism, nanoscale cross-relaxation spectroscopy of both electron and nuclear spins in the vicinity of the NV centre are performed. We then show that through maintaining the magnet at a constant temperature an order of magnitude improvement in the stability of the NV qubit frequency can be achieved. This improved stability is tested in the polarisation of a small ensemble of nearby $^{13}$C spins via resonant cross-relaxation and the lifetime of this polarisation explored. The effectiveness and relative simplicity of this technique may find use in the realisation of portable spectroscopy and/or hyperpolarisation systems.

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David A. Broadway, Scott E. Lillie, Nikolai Dontschuk, Alastair Stacey, Liam T. Hall, Jean-Philippe Tetienne, Lloyd C. L. Hollenberg. 2017-12-23. High precision single qubit tuning via thermo-magnetic field control. https://doi.org/10.1063/1.5021491

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