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arXiv · 2403.07446

Compact structures for single-beam magneto-optical trapping of ytterbium

Abstract

Today's best optical lattice clocks are based on the spectroscopy of trapped alkaline-earth-like atoms such as ytterbium and strontium atoms. The development towards mobile or even space-borne clocks necessitates concepts for the compact laser-cooling and trapping of these atoms with reduced laser requirements. Here we present two compact and robust achromatic mirror structures for single-beam magneto-optical trapping of alkaline-earth-like atoms using two widely separated optical cooling frequencies. We have compared the trapping and cooling performance of a monolithic aluminium structure that generates a conventional trap geometry to a quasi-planar platform based on a periodic mirror structure for different isotopes of Yb. Compared to prior work with strontium in non-conventional traps, where only bosons were trapped on a narrow line transition, we demonstrate two-stage cooling and trapping of a fermionic alkaline-earth-like isotope in a single-beam quasi-planar structure.

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Julian Pick, Roman Schwarz, Jens Kruse, Christian Lisdat, Carsten Klempt. 2024-03-12. Compact structures for single-beam magneto-optical trapping of ytterbium. https://arxiv.org/abs/2403.07446

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