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arXiv · 1606.06600

Near-Infrared-Assisted Charge Control and Spin Readout of the Nitrogen-Vacancy Center in Diamond

David A. Hopper·Richard R. Grote·Annemarie L. Exarhos·Lee C. Bassett
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Abstract

We utilize nonlinear absorption to design all-optical protocols that improve both charge state initialization and spin readout for the nitrogen-vacancy (NV) center in diamond. Non-monotonic variations in the equilibrium charge state as a function of visible and near-infrared (NIR) optical power are attributed to competing multiphoton absorption processes. In certain regimes, multicolor illumination enhances the steady-state population of the NV's negative charge state above 90%. At higher NIR intensities, selective ionization of the singlet manifold facilitates a protocol for spin-to-charge conversion that dramatically enhances the spin readout fidelity. We demonstrate a 6-fold increase in the signal-to-noise ratio for single-shot spin measurements and predict an orders-of-magnitude experimental speedup over traditional methods for emerging applications in magnetometry and quantum information science using NV spins.

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David A. Hopper, Richard R. Grote, Annemarie L. Exarhos, Lee C. Bassett. 2016-08-04. Near-Infrared-Assisted Charge Control and Spin Readout of the Nitrogen-Vacancy Center in Diamond. https://doi.org/10.1103/physrevb.94.241201

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