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Polarization and readout of coupled single spins in diamond

R. Hanson·F. M. Mendoza·R. J. Epstein·D. D. Awschalom
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Abstract

We study the coupling of a single nitrogen-vacancy center in diamond to a nearby single nitrogen defect at room temperature. The magnetic dipolar coupling leads to a splitting in the electron spin resonance frequency of the nitrogen-vacancy center, allowing readout of the state of a single nitrogen electron spin. At magnetic fields where the spin splitting of the two centers is the same we observe a strong polarization of the nitrogen electron spin. The amount of polarization can be controlled by the optical excitation power. We combine the polarization and the readout in time-resolved pump-probe measurements to determine the spin relaxation time of a single nitrogen electron spin. Finally, we discuss indications for hyperfine-induced polarization of the nitrogen nuclear spin.

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R. Hanson, F. M. Mendoza, R. J. Epstein, D. D. Awschalom. 2006-08-23. Polarization and readout of coupled single spins in diamond. https://doi.org/10.1103/physrevlett.97.087601

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