2025/07/15 by Michael Vayninger, Vayninger, Michael, Angela Xiang +15
Physics and Astronomy · #Advanced Frequency and Time Standards #Atomic Physics (physics.atom-ph) #Cold Atom Physics and Bose-Einstein Condensates #FOS: Physical sciences #Quantum Gases (cond-mat.quant-gas)
paper · pdf · doi:10.48550/arxiv.2507.11434
openalex publication_date 2025/07/15 · openalex created_date 2025/10/09 · openalex updated_date 2026/08/01
We demonstrate a dual magneto-optical trap of 109Ag and 39K. For silver, a decreasing-field Zeeman slower loads a MOT of 1.5×108 atoms at a temperature of 0.74(5) mK, with laser cooling occurring primarily on the D2 line of 4d105s 2S1/2→ 5p 2P3/2 at 328 nm. We create a novel Ag "dark spot MOT," where shelving the atoms in a dark state enhances the captured atom number by a factor of two and the lifetime by a factor of four. For potassium, we obtain 2×108 trapped atoms, and further cooling on the D1 transition via grey molasses results in a cloud of 1.2× 108 atoms at 7(1) μK. We observe evidence of photoionization loss of the K MOT in the presence of Ag laser-cooling light, with implications for optimal dual species loading strategies. Our results on Ag point to simple and general laser cooling strategies for other coinage metals (Au, Cu). Furthermore, this work lays the foundation for the production of alkali-coinage metal degenerate quantum mixtures and highly polar molecules.