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arXiv · 2111.04047

Comparing Two-Qubit and Multi-Qubit Gates within the Toric Code

David Schwerdt·Yotam Shapira·Tom Manovitz·Roee Ozeri
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Abstract

In some quantum computing (QC) architectures, entanglement of an arbitrary number of qubits can be generated in a single operation. This property has many potential applications, and may specifically be useful for quantum error correction (QEC). Stabilizer measurements can then be implemented using a single multi-qubit gate instead of several two-qubit gates, thus reducing circuit depth. In this study, the toric code is used as a benchmark to compare the performance of two-qubit and five-qubit gates within parity-check circuits. We consider trapped ion qubits that are controlled via Raman transitions, where the primary source of error is assumed to be spontaneous photon scattering. We show that a five-qubit M{\o}lmer-S{\o}rensen gate offers an approximately $40\%$ improvement over two-qubit gates in terms of the fault tolerance threshold. This result indicates an advantage of using multi-qubit gates in the context of QEC.

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David Schwerdt, Yotam Shapira, Tom Manovitz, Roee Ozeri. 2021-11-07. Comparing Two-Qubit and Multi-Qubit Gates within the Toric Code. https://doi.org/10.1103/physreva.105.022612

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