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arXiv · 2110.01590

Five-second coherence of a single spin with single-shot readout in silicon carbide

Christopher P. Anderson·Elena O. Glen·Cyrus Zeledon·Alexandre Bourassa·Yu Jin·Yizhi Zhu·Christian Vorwerk·Alexander L. Crook·Hiroshi Abe·Jawad Ul-Hassan·Takeshi Ohshima·Nguyen T. Son·Giulia Galli·David D. Awschalom
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Abstract

An outstanding hurdle for defect spin qubits in silicon carbide (SiC) is single-shot readout - a deterministic measurement of the quantum state. Here, we demonstrate single-shot readout of single defects in SiC via spin-to-charge conversion, whereby the defect's spin state is mapped onto a long-lived charge state. With this technique, we achieve over 80% readout fidelity without pre- or post-selection, resulting in a high signal-to-noise ratio (SNR) that enables us to measure long spin coherence times. Combined with pulsed dynamical decoupling sequences in an isotopically purified host material, we report single spin T2 > 5s, over two orders of magnitude greater than previously reported in this system. The mapping of these coherent spin states onto single charges unlocks both single-shot readout for scalable quantum nodes and opportunities for electrical readout via integration with semiconductor devices.

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Christopher P. Anderson, Elena O. Glen, Cyrus Zeledon, Alexandre Bourassa, Yu Jin, Yizhi Zhu, Christian Vorwerk, Alexander L. Crook, Hiroshi Abe, Jawad Ul-Hassan, Takeshi Ohshima, Nguyen T. Son, Giulia Galli, David D. Awschalom. 2021-10-04. Five-second coherence of a single spin with single-shot readout in silicon carbide. https://arxiv.org/abs/2110.01590

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