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arXiv · 1502.07621

Optical polarization of nuclear spins in silicon carbide

Abram L. Falk·Paul V. Klimov·Viktor Ivády·Krisztián Szász·David J. Christle·William F. Koehl·Ádám Gali·David D. Awschalom
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Abstract

We demonstrate optically pumped dynamic nuclear polarization of 29-Si nuclear spins that are strongly coupled to paramagnetic color centers in 4H- and 6H-SiC. The 99 +/- 1% degree of polarization at room temperature corresponds to an effective nuclear temperature of 5 microKelvin. By combining ab initio theory with the experimental identification of the color centers' optically excited states, we quantitatively model how the polarization derives from hyperfine-mediated level anticrossings. These results lay a foundation for SiC-based quantum memories, nuclear gyroscopes, and hyperpolarized probes for magnetic resonance imaging.

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Abram L. Falk, Paul V. Klimov, Viktor Ivády, Krisztián Szász, David J. Christle, William F. Koehl, Ádám Gali, David D. Awschalom. 2015-02-26. Optical polarization of nuclear spins in silicon carbide. https://doi.org/10.1103/physrevlett.114.247603

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