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arXiv · 2407.09349

Exactly-solved model of light-scattering errors in quantum simulations with metastable trapped-ion qubits

Phillip C. Lotshaw·Brian C. Sawyer·Creston D. Herold·Gilles Buchs
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Abstract

We analytically solve a model for light scattering in Ising dynamics of metastable atomic qubits, generalizing the approach of Foss-Feig {\it et al.}~[Phys.~Rev.~A {\bf 87}, 042101 (2013)] to include leakage outside the qubit manifold. We analyze the influence of these fundamental errors in simulations of proposed experiments with metastable levels of $^{40}$Ca$^+$ ions. We find that ``effective magnetic fields" generated by leaked qubits have significant impacts on spin-spin correlation functions for Greenberger-Horne-Zeilinger state preparation or for quantum simulations with strong coupling, while spin squeezing uses a much weaker coupling and is largely insensitive to the simulated leakage errors, even with a few hundred ions. Our theory and results are expected to be useful in modeling a variety of metastable qubit experiments in the future.

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Phillip C. Lotshaw, Brian C. Sawyer, Creston D. Herold, Gilles Buchs. 2024-07-12. Exactly-solved model of light-scattering errors in quantum simulations with metastable trapped-ion qubits. https://doi.org/10.1103/physreva.110.l030803

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