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Programmable optical tweezer arrays of molecules are an emerging platform for quantum simulation and quantum information science. For these applications, the reduction and mitigation of errors remain major challenges. In this work, we leverage the rich internal structure of molecules to mitigate two types of errors - internal state preparation and qubit leakage errors. First, we demonstrate robust measurement-enhanced tweezer preparation at a record fidelity using site-resolved error detection followed by tweezer movement. Second, using a new hyperfine qubit encoding well-suited for use as a quantum memory, we demonstrate site-resolved detection of qubit leakage errors (erasures) induced by blackbody radiation. This constitutes the first demonstration of erasure conversion in molecules, a capability that has found recent interest in quantum error correction. Our work opens the door to new possibilities with molecular tweezer arrays: Measurement-enhanced preparation opens access to mesoscopic defect-free molecular arrays that are important for quantum simulation of interacting many-body systems; erasure conversion in molecular arrays lays the technical ground- work for mid-circuit detection, an important capability for explorations in quantum information processing.
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Imaging a Li6 Atom in an Optical Tweezer 2000 Times with Λ-Enhanced Gray Molasses
We have imaged lithium-6 thousands of times in an optical tweezer using Λ-enhanced gray molasses cooling light. Despite being the lightest alkali metal, with a recoil temperature of 3.5 μK, we achieve an imaging survival of 0.999 50(2), which sets the new benchmark for low-loss imaging of neutral atoms in optical tweezers. Lithium is loaded directly from a magneto-optical trap into a tweezer with an enhanced loading rate of 0.7. We cool the atom to 70 μK and present a new cooling model that accurately predicts steady-state temperature and scattering rate in the tweezer. These results pave the way for ground state preparation of lithium en route to the assembly of the LiCs molecule in its ground state.
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- Award ID(s):
- 2239961
- PAR ID:
- 10518010
- Publisher / Repository:
- American Physical Society
- Date Published:
- Journal Name:
- Physical Review Letters
- Volume:
- 131
- Issue:
- 8
- ISSN:
- 0031-9007
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1103/PhysRevLett.131.083001
