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arXiv · 2303.02084

Fault-tolerant qubit encoding using a spin-7/2 qudit

Sumin Lim·Junjie Liu·Arzhang Ardavan
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Abstract

The implementation of error correction protocols is a central challenge in the development of practical quantum information technologies. Recently, multi-level quantum resources such as harmonic oscillators and qudits have attracted interest in this context because they offer the possibility of additional Hilbert space dimensions in a spatially compact way. Here we propose a quantum memory, implemented on a spin-7/2 nucleus hyperfine-coupled to an electron spin-1/2 qubit, which provides first order $X$, $Y$ and $Z$ error correction using significantly fewer quantum resources than the equivalently effective qubit-based protocols. Our encoding may be efficiently implemented in existing experimentally realised molecular electron-nuclear quantum spin systems. The strategy can be extended to higher-order error protection on higher-spin nuclei.

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Sumin Lim, Junjie Liu, Arzhang Ardavan. 2023-03-03. Fault-tolerant qubit encoding using a spin-7/2 qudit. https://doi.org/10.1103/physreva.108.062403

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