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Loading and Imaging Atom Arrays via Electromagnetically Induced Transparency

Emily H. Qiu1,*, Tamara Šumarac2,1,*, Peiran Niu1,*, Shai Tsesses1, Fadi Wassaf1,3, David C. Spierings1, Meng-Wei Chen1, Mehmet T. Uysal1, Audrey Bartlett1,4 et al.

Adrian J. Menssen1, Mikhail D. Lukin2, and Vladan Vuletić1,†

  • *These authors contributed equally.
  • †Contact author: vuletic@mit.edu
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PRX Quantum 7, 020358 – Published 12 June, 2026

DOI: https://doi.org/10.1103/fd15-4g1n

Abstract

Arrays of neutral atoms present a promising system for quantum computing, quantum sensors, and other applications, several of which would profit from the ability to load, cool, and image the atoms in a finite magnetic field. In this work, we develop a technique to image and prepare 87Rb atom arrays in a finite magnetic field by combining electromagnetically induced transparency cooling with fluorescence imaging. We achieve an average readout fidelity of 99.7(1)% at 98.2(3)% survival probability and up to 68(2)% single-atom stochastic loading probability in a 2.3 G magnetic field, with performance validated at fields up to 10 G. We further develop a model to predict the survival probability, which also agrees well with several other atom-array experiments. Our technique cools both the axial and radial directions, and will enable future continuously operated neutral-atom quantum processors and quantum sensors.

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Popular Summary

Neutral-atom arrays trapped in optical tweezers have emerged as a leading architecture for quantum information processing. However, scaling neutral-atom quantum processors is bottlenecked by the constant need to ramp the magnetic fields. While stable and uniform bias fields are required to perform coherent qubit operations, traditional sub-Doppler cooling and imaging requires a zero-magnetic-field environment (particularly for alkali atoms). Dynamically ramping these fields not only limits the duty cycle of the processor, but also restricts capabilities for mid-circuit readout and on-the-fly qubit reloading. In this work, the authors overcome this limitation by demonstrating a new technique to load, cool, and image 87Rb atom arrays in constant bias magnetic fields (up to 10 G). By combining electromagnetically induced transparency cooling with simultaneous fluorescence imaging, they achieve high readout fidelity and high atom survival rate. Furthermore, by engineering light-assisted atomic collisions, the same technique is used to prepare single atoms in tweezers with enhanced probability, which is crucial for next-generation continuously operated quantum processors based on large arrays of neutral atoms. To explain remaining imaging-induced atom losses, the authors develop a semiquantitative model based on collisions between trapped, electronically excited atoms, and hot background atoms in the vacuum chamber. This model is further validated by comparing data across a variety of atom-array experiments, offering important implications for low-loss imaging in neutral-atom arrays. By demonstrating many of the key ingredients for operating neutral-atom arrays—including loading, cooling, and imaging single atoms in a constant magnetic field—this work paves the path toward continuously operated, fault-tolerant neutral-atom quantum processors.

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PRX Quantum 7, 020358– Published 12 June, 2026
  • Received 15 September 2025
  • Revised 1 April 2026
  • Accepted 7 May 2026
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