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arXiv · 2502.05362

First-principle crosstalk dynamics and Hamiltonian learning via Rabi experiments

Jan Balewski·Adam Winick·Yilun Xu·Neel Vora·Gang Huang·David Santiago·Joseph Emerson·Irfan Siddiqi
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Abstract

Coherent errors constitute a significant barrier to successful large-scale quantum computation. One such error mechanism is crosstalk, which violates spatial locality or the independence of operations. We present a description of crosstalk and learn the underlying parameters by executing novel simultaneous Rabi experiments and fitting the Hamiltonian to the observed data. We use this model to predict three- and four-qubit experiments and observe excellent agreement between our theoretical predictions and experimental results. Our technique enables researchers to study the dynamics of multi-qubit circuits without performing experiments, potentially facilitating the minimization of coherent gate errors via digital pulse precompilation. Additionally, this method provides whole-chip crosstalk characterization, a useful tool for guiding quantum processor design.

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Jan Balewski, Adam Winick, Yilun Xu, Neel Vora, Gang Huang, David Santiago, Joseph Emerson, Irfan Siddiqi. 2025-02-07. First-principle crosstalk dynamics and Hamiltonian learning via Rabi experiments. https://arxiv.org/abs/2502.05362

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