atommovr: An open-source simulation framework for rearrangement in atomic arrays

Nikhil K Harle; Bo-Yu Chen; Bob Bao; Hannes Bernien

doi:10.22331/q-2026-07-29-2177

atommovr: An open-source simulation framework for rearrangement in atomic arrays

Nikhil K Harle^1,2, Bo-Yu Chen^1,3,4, Bob Bao^5,6, and Hannes Bernien^1,3,7

¹Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL 60637, USA
²JILA, University of Colorado and National Institute of Standards and Technology, and Department of Physics, University of Colorado, Boulder, CO 80309, USA
³Institute for Quantum Optics and Quantum Information, Austrian Academy of Sciences, 6020 Innsbruck, Austria
⁴Department of Physics and Department of Computer Science and Information Engineering, National Taiwan University, Taipei 10617, Taiwan
⁵Department of Physics, University of Chicago, Chicago, IL 60637, USA
⁶Quantum Science and Engineering, Harvard Griffin Graduate School of Arts and Sciences, Harvard University, Cambridge, MA 02138, USA
⁷Institute for Experimental Physics, University of Innsbruck, 6020 Innsbruck, Austria

Published:	2026-07-29, volume 10, page 2177
Editor:	Tommaso Macrì
Eprint:	arXiv:2508.02670v2
Doi:	https://doi.org/10.22331/q-2026-07-29-2177
Citation:	Quantum 10, 2177 (2026).

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Abstract

The task of atom rearrangement has emerged in the last decade as a fundamental building block in the development of neutral atom-based quantum processors. As such processors grow to thousands of atoms, it becomes increasingly important to design algorithms robust to experimental sources of error. While recent progress has been made towards developing algorithms with favorable time scaling, such work has been limited to noiseless settings. Moreover, there is a lack of open-source code for reproducing and benchmarking existing algorithms. To address these deficiencies, we develop an open-source simulation framework, atommovr, and leverage it to study three distinct settings: 1) time-optimal, noiseless rearrangement, 2) noisy rearrangement under realistic error models, and 3) noiseless dual-species rearrangement. We extract lower bounds for time-optimal rearrangement, study advantageous strategies across different error regimes, and develop a novel dual-species algorithm, InsideOut, capable of avoiding 'blocked' configurations with a near-unity success rate. We hope that atommovr can serve as a common tool for the community to study rearrangement, lower the barrier to entry for new experimental groups, and stimulate progress in developing algorithms tailored to minimize atom loss in experiment.

Featured image: $\href{https://github.com/bernienlab/atommovr}{\text{atommovr}}$

Popular summary

Neutral atoms confined by tightly focused beams of light called 'optical tweezers' are a promising prototype for a quantum computer. Hundreds or thousands of atoms can be trapped this way, and arranged into a grid to form a register of quantum bits.

However, there is a catch in how this register is formed. Tweezers are loaded by being overlapped with a cold cloud of atoms, and the loading is probabilistic: what comes out is a grid with random gaps in it. Before a computation can begin, the trapped atoms must be shuffled around to form a regular configuration.

But this shuffling is a race: each move operation takes time and risks spilling the atom, and the atoms typically survive only for seconds to tens of minutes before being hit by background gas particles. The problem of how to efficiently sort atoms is called 'rearrangement'.

Here, we develop $\text{atommovr}$, an open-source Monte Carlo simulation framework for evaluating rearrangement algorithms and measuring how they hold up against the atom losses and timing constraints of a real experiment.

$\text{atommovr}$ is designed to be built upon by the community. Up-to-date information concerning new features and opportunities for contribution can be found on the project's $\href{https://github.com/bernienlab/atommovr}{\text{GitHub}}$ page.

► BibTeX data

@article{Harle2026atommovropensource,
  doi = {10.22331/q-2026-07-29-2177},
  url = {https://doi.org/10.22331/q-2026-07-29-2177},
  title = {atommovr: {A}n open-source simulation framework for rearrangement in atomic arrays},
  author = {Harle, Nikhil K and Chen, Bo-Yu and Bao, Bob and Bernien, Hannes},
  journal = {{Quantum}},
  issn = {2521-327X},
  publisher = {{Verein zur F{\"{o}}rderung des Open Access Publizierens in den Quantenwissenschaften}},
  volume = {10},
  pages = {2177},
  month = jul,
  year = {2026}
}

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