Blinking optical tweezers for atom rearrangements

Scalable rearrangement of the atom array is essential for preparation and manipulation of large qubit systems [1,2]. We propose and experimentally demonstrate an efficient method to hold and rearrange M single atoms using a single optical tweezer. By blinking the harmonic trap potential on and off with the period derived from the trap frequency [3,4], the atom's probability distribution on the phase space remains preserved. This approach allows a single blinking tweezer to consecutively recapture M atom. From the experimental radial trap frequency ω = 2π × 64(5) kHz, we derive the blinking resonance condition as 1.1 μs trap-on time for a 10 μs trap-off time. Under these conditions, proof-of-principle experiments confirm that a single blinking optical tweezer could trap M=9 ⁸⁷Rb atoms. Furthermore, the method demonstrates the ability to rearrange atoms in various configurations, such as array rotation and worm running, similar to scenarios explored in our previous work [5]. Blinking tweezer arrays provide a method to conserve beam power by 1/M while maintaining the size of the atom array. Moreover, they allow for individual control of atoms, supporting operations like rearrangement process, all while ensuring scalability.

[1] A. M. Kaufman and K.-K. Ni, “Quantum science with optical tweezer arrays of ultracold atoms and molecules,” Nat. Phys. 17, 1324 (2021).

[2] R. Lin et al., “AI-Enabled Rapid Assembly of Thousands of Defect-Free Neutral Atom Arrays with Constant-Time-Overhead,” arXiv:2412.14647 (2024).

[3] M. Morinaga, I. Bouchoule, J.-C. Karam, and C. Salomon, “Manipulation of Motional Quantum States of Neutral Atoms,” Phys. Rev. Lett. 83, 4037 (1999).

[4] H. Ammann, and N. Christensen, “Delta Kick Cooling: A New Method for Cooling Atoms,” Phys. Rev. Lett. 78, 2088 (1997).

[5] W. Lee, H. Kim, and J. Ahn, “Three-dimensional rearrangement of single atoms using actively controlled optical microtraps,” Optics Express 24, 9816 (2016).