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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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Simulated optical molasses cooling of trapped antihydrogen
Abstract We theoretically and computationally investigate the cooling of antihydrogen, ¯H, using optical molasses cooling. This updates the results in Ref. [1] to the current capabilities of the ALPHA experiment. Through Monte Carlo simulation, we show that ¯Hs do not give the standard cooling even in an ideal optical molasses because of their small mass and large transition frequency. For optical molasses cooling in the ALPHA trap, the photons are constrained to travel in one direction only. It is only through the phase space mixing in the trap that cooling in all directions can be achieved. We explore the nontrivial role that laser intensity plays in the cooling. We also investigate the possibility for simultaneously cooling atoms in either of the trapped ground states.
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- PAR ID:
- 10568609
- Publisher / Repository:
- IOP Publishing
- Date Published:
- Journal Name:
- Journal of Physics B: Atomic, Molecular and Optical Physics
- ISSN:
- 0953-4075
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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