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arXiv · 2504.06182

Efficient algorithms to solve atom reconfiguration problems. III. The bird and batching algorithms and other parallel implementations on GPUs

Fouad Afiouni·Remy El Sabeh·Naomi Nishimura·Izzat El Hajj·Amer E. Mouawad·Alexandre Cooper
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Abstract

We present efficient implementations of atom reconfiguration algorithms for both CPUs and GPUs, along with a batching routine to merge displacement operations for parallel execution. Leveraging graph-theoretic methods, our approach derives improved algorithms that achieve reduced time complexity and faster operational running times. First, we introduce an enhanced version of the redistribution-reconfiguration (red-rec) algorithm, which offers superior operational and runtime performance. We detail its efficient implementation on a GPU using a parallel approach. Next, we present an optimized version of the assignment-reconfiguration-ordering (aro) algorithm, specifically tailored for unweighted grid graphs. Finally, we introduce the bird algorithm to solve reconfiguration problems on grids, achieving performance gains over both red-rec and aro. These algorithms can be used to prepare defect-free configurations of neutral atoms in arrays of optical traps, serve as subroutines in more complex algorithms, or cross-benchmark the operational and runtime performance of new algorithms. They are suitable for realizing quantum circuits incorporating displacement operations and are optimized for real-time operation on increasingly large system sizes.

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Fouad Afiouni, Remy El Sabeh, Naomi Nishimura, Izzat El Hajj, Amer E. Mouawad, Alexandre Cooper. 2025-04-08. Efficient algorithms to solve atom reconfiguration problems. III. The bird and batching algorithms and other parallel implementations on GPUs. https://arxiv.org/abs/2504.06182

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