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arXiv · 1701.06848

Coherent control of the silicon-vacancy spin in diamond

Benjamin Pingault·David-Dominik Jarausch·Christian Hepp·Lina Klintberg·Jonas N. Becker·Matthew Markham·Christoph Becher·Mete Atatüre
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Abstract

Spin impurities in diamond have emerged as a promising building block in a wide range of solid-state-based quantum technologies. The negatively charged silicon-vacancy centre combines the advantages of its high-quality photonic properties with a ground-state electronic spin, which can be read out optically. However, for this spin to be operational as a quantum bit, full quantum control is essential. Here, we report the measurement of optically detected magnetic resonance and the demonstration of coherent control of a single silicon-vacancy centre spin with a microwave field. Using Ramsey interferometry, we directly measure a spin coherence time, T2*, of 115 +/- 9 ns at 3.6 K. The temperature dependence of coherence times indicates that dephasing and decay of the spin arise from single phonon-mediated excitation between orbital branches of the ground state. Our results enable the silicon-vacancy centre spin to become a controllable resource to establish spin-photon quantum interfaces.

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Benjamin Pingault, David-Dominik Jarausch, Christian Hepp, Lina Klintberg, Jonas N. Becker, Matthew Markham, Christoph Becher, Mete Atatüre. 2017-01-24. Coherent control of the silicon-vacancy spin in diamond. https://doi.org/10.1038/ncomms15579

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