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arXiv · 1708.08852

Silicon-Vacancy Spin Qubit in Diamond: A Quantum Memory Exceeding 10 ms with Single-Shot State Readout

Denis D. Sukachev·Alp Sipahigil·Christian T. Nguyen·Mihir K. Bhaskar·Ruffin E. Evans·Fedor Jelezko·Mikhail D. Lukin
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Abstract

The negatively-charged silicon-vacancy (SiV$^-$) color center in diamond has recently emerged as a promising system for quantum photonics. Its symmetry-protected optical transitions enable creation of indistinguishable emitter arrays and deterministic coupling to nanophotonic devices. Despite this, the longest coherence time associated with its electronic spin achieved to date ($\sim 250$ ns) has been limited by coupling to acoustic phonons. We demonstrate coherent control and suppression of phonon-induced dephasing of the SiV$^-$ electronic spin coherence by five orders of magnitude by operating at temperatures below 500 mK. By aligning the magnetic field along the SiV$^-$ symmetry axis, we demonstrate spin-conserving optical transitions and single-shot readout of the SiV$^-$ spin with 89% fidelity. Coherent control of the SiV$^-$ spin with microwave fields is used to demonstrate a spin coherence time $T_2$ of 13 ms and a spin relaxation time $T_1$ exceeding 1 s at 100 mK. These results establish the SiV$^-$ as a promising solid-state candidate for the realization of scalable quantum networks.

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Denis D. Sukachev, Alp Sipahigil, Christian T. Nguyen, Mihir K. Bhaskar, Ruffin E. Evans, Fedor Jelezko, Mikhail D. Lukin. 2017-12-04. Silicon-Vacancy Spin Qubit in Diamond: A Quantum Memory Exceeding 10 ms with Single-Shot State Readout. https://doi.org/10.1103/physrevlett.119.223602

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