Analytical blueprint for 99.999% fidelity X-gates on present superconducting hardware under strong driving

• URL: http://arxiv.org/abs/2512.19919v1
• Date: Mon, 22 Dec 2025 22:47:43 GMT
• Title: Analytical blueprint for 99.999% fidelity X-gates on present superconducting hardware under strong driving
• Abstract summary: We numerically demonstrate gate infidelities below $10-5$ for a 7ns $$-rotation when incorporating existing decoherence rates.<n>We also answer long-standing questions about the optimal values of the DRAG prefactor as well as constant detuning.
• Score: 4.406638884109584
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: Achieving very fast gates that undercut the natural limits set by decoherence requires going into the strong driving limit. Realizing single-qubit control predicted beyond semi-classical, time-dependent modeling has yet to be experimentally realized on superconducting and most other computing platforms. In this regime, the common model of dynamics within a three-level manifold breaks down, and instead, we see new quantum error channels growing abruptly with decreasing time. To identify these error processes we systematically calculate the effect of multi-photon transitions that occur out of the computational space. We then derive analytical formulas to suppress these effects, as well as amplitude and phase errors on the qubit space; we term these R1D for suppressing the $|0\rangle-|2\rangle$ transition and R2D when also suppressing $|1\rangle-|3\rangle$ leakage. We also answer long-standing questions about the optimal values of the DRAG prefactor as well as constant detuning, when accounting for time-ordering, and also show how to calibrate other prefactors for further performance improvement. Upon correcting these varied sources of error, we numerically demonstrate gate infidelities below $10^{-5}$ for a 7ns $π$-rotation when incorporating existing decoherence rates.

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