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Fast Single-Atom Preparation in Optical Tweezers via Rydberg Blockade

Yiyi Li1,*, Vernon M. Hughes1,2,*, Michael Peper1, Yicheng Bao1, Chenyuan Li1,2, Sanzhar Bissenali1,3, and Jeff D. Thompson1,†

  • *These authors contributed equally to this work.
  • †Contact author: jdthompson@princeton.edu
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PRX Quantum 7, 043019 – Published 28 October, 2026

DOI: https://doi.org/10.1103/8t3p-x6s7

Abstract

Continuously replenished optical tweezer arrays will unlock unlimited-depth quantum circuits with neutral atom qubits. A key bottleneck limiting the cycle time of these systems is removing atoms from tweezers initially loaded with more than one atom. In the conventional technique of light-assisted collisions, slow collisional dynamics limit the timescale for removing excess atoms to several milliseconds. Here, we propose and demonstrate a scheme for selectively removing one atom at a time from multiply occupied tweezers on a microsecond timescale, using intra-tweezer Rydberg blockade and autoionization. We demonstrate the protocol in Yb171 in two complementary regimes. With two-photon Rydberg excitation from the ground state, we reduce the multi-atom probability to 1% in 64.8  μs, while retaining single atoms in 58.2(2)% of the tweezers, which is comparable to the filling fraction achieved with light-assisted collisions under the same experimental conditions, but over two orders of magnitude faster. With single-photon excitation from the metastable state P03, reduced single-atom loss enables a higher filling fraction of 74.8(3)%, at the cost of additional temporal overhead to prepare the atoms in P03. The final filling fraction is limited by an unexplained two-body loss mechanism, which, if solved, could enable fast, quasi-deterministic loading.

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Popular Summary

As neutral-atom quantum computers move toward increasingly deep quantum circuits, reducing the time required for each operation has become an important frontier. Recent advances in neutral-atom control have pushed the timescales of many operations to the millisecond-scale. Preparing a single atom from an optical tweezer that contains multiple atoms, however, still typically takes about 10 ms; conventional techniques rely on slow atomic collisions to reduce a stochastically loaded number of atoms to one. In this work, we propose and experimentally demonstrate a faster approach that uses strong interactions between highly excited atoms to selectively remove excess atoms one at a time. We demonstrate removal of multiple atoms in a tweezer in under 100  μs, about 100 times faster than conventional approaches, eliminating single-atom preparation from among the slowest steps in current neutral-atom experiments. Further improvements of this protocol may also enable rapid preparation of large, defect-free arrays of atoms without the slow process of atom rearrangement.

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PRX Quantum 7, 043019– Published 28 October, 2026
  • Received 10 June 2026
  • Accepted 21 September 2026
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