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arXiv · 2510.09508

Subspace Leakage Error Randomized Benchmarking of M{\o}lmer-S{\o}rensen Gates

R. T. Sutherland·A. C. Hughes·J. P. Marceaux·H. M. Knaack·C. M. Löschnauer·R. Srinivas
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Abstract

We demonstrate a new technique that adapts single-qubit randomized benchmarking to two-qubit M{\o}lmer-S{\o}rensen gates. We use the controllable gate phase to generate Cliffords that act on a two-state subspace, enabling benchmarking of two-qubit gates without single-qubit operations. In addition to quantifying the gate infidelity, the protocol provides valuable information about the type of error by distinguishing between those that conserve the two-state subspace and those that result in leakage out of it. We demonstrate the protocol for calibrating and validating all-electronic maximally entangling gates in a trapped-ion quantum computer, achieving a two-qubit gate error of $2.6 (2)\times10^{-4}$.

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R. T. Sutherland, A. C. Hughes, J. P. Marceaux, H. M. Knaack, C. M. Löschnauer, R. Srinivas. 2025-10-10. Subspace Leakage Error Randomized Benchmarking of M{\o}lmer-S{\o}rensen Gates. https://arxiv.org/abs/2510.09508

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