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arXiv · 1410.0370

Efficient readout of a single spin state in diamond via spin-to-charge conversion

B. J. Shields·Q. P. Unterreithmeier·N. P. de Leon·H. Park·M. D. Lukin
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Abstract

Efficient readout of individual electronic spins associated with atom-like impurities in the solid state is essential for applications in quantum information processing and quantum metrology. We demonstrate a new method for efficient spin readout of nitrogen-vacancy (NV) centers in diamond. The method is based on conversion of the electronic spin state of the NV to a charge state distribution, followed by single-shot readout of the charge state. Conversion is achieved through a spin-dependent photoionization process in diamond at room temperature. Using NVs in nanofabricated diamond beams, we demonstrate that the resulting spin readout noise is within a factor of three of the spin projection noise level. Applications of this technique for nanoscale magnetic sensing are discussed.

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B. J. Shields, Q. P. Unterreithmeier, N. P. de Leon, H. Park, M. D. Lukin. 2014-10-01. Efficient readout of a single spin state in diamond via spin-to-charge conversion. https://doi.org/10.1103/physrevlett.114.136402

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