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arXiv · 2401.04465

High fidelity optical readout of a nuclear spin qubit in Silicon Carbide

Erik Hesselmeier·Oliver von Berg·Pierre Kuna·Wolfgang Knolle·Florian Kaiser·Nguyen Tien Son·Misagh Ghezellou·Jawad Ul-Hassan·Vadim Vorobyov·Jörg Wrachtrup
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Abstract

Quantum state readout is a key requirement for a successful qubit platform. In this work we demonstrate a high fidelity quantum state readout of a V2 center nuclear spin based on a repetitive readout technique. We demonstrate up to 99.5$\,\%$ readout fidelity and 99$\,\%$ for state preparation. Using this efficient readout we initialise the nuclear spin by measurement and demonstrate its Rabi and Ramsey nutation. Finally, we use the nuclear spin as a long lived memory for quantum sensing application of weakly coupled diatomic nuclear spin bath.

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Erik Hesselmeier, Oliver von Berg, Pierre Kuna, Wolfgang Knolle, Florian Kaiser, Nguyen Tien Son, Misagh Ghezellou, Jawad Ul-Hassan, Vadim Vorobyov, Jörg Wrachtrup. 2024-03-08. High fidelity optical readout of a nuclear spin qubit in Silicon Carbide. https://arxiv.org/abs/2401.04465

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