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arXiv · 2009.14172

High-fidelity single-shot readout of single electron spin in diamond with spin-to-charge conversion

Qi Zhang·Yuhang Guo·Wentao Ji·Mengqi Wang·Jun Yin·Fei Kong·Yiheng Lin·Chunming Yin·Fazhan Shi·Ya Wang·Jiangfeng Du
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Abstract

High fidelity single-shot readout of qubits is a crucial component for fault-tolerant quantum computing and scalable quantum networks. In recent years, the nitrogen-vacancy (NV) center in diamond has risen as a leading platform for the above applications. The current single-shot readout of the NV electron spin relies on resonance fluorescence method at cryogenic temperature. However, the the spin-flip process interrupts the optical cycling transition, therefore, limits the readout fidelity. Here, we introduce a spin-to-charge conversion method assisted by near-infrared (NIR) light to suppress the spin-flip error. This method leverages high spin-selectivity of cryogenic resonance excitation and high flexibility of photonionization. We achieve an overall fidelity $>$ 95% for the single-shot readout of an NV center electron spin in the presence of high strain and fast spin-flip process. With further improvements, this technique has the potential to achieve spin readout fidelity exceeding the fault-tolerant threshold, and may also find applications on integrated optoelectronic devices.

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quant-phphysics.app-phphysics.optics

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Qi Zhang, Yuhang Guo, Wentao Ji, Mengqi Wang, Jun Yin, Fei Kong, Yiheng Lin, Chunming Yin, Fazhan Shi, Ya Wang, Jiangfeng Du. 2020-09-29. High-fidelity single-shot readout of single electron spin in diamond with spin-to-charge conversion. https://doi.org/10.1038/s41467-021-21781-5

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