Experimental apparatus for generating quantum degenerate gases of ytterbium atoms
Tóm tắt
We describe our experimental apparatus for generating quantum degenerate gases of bosonic 174Yb and fermionic 173Yb atoms. We use a Zeeman slower to generate a slow atomic beam and collect atoms in a magneto-optical trap formed by 556-nm laser beams without frequency modulations. Laser-cooled ytterbium atoms are transferred to a crossed optical dipole trap and evaporatively cooled to quantum degeneracy. Our system generates a Bose-Einstein condensate containing over 6 × 104
174Yb atoms or a degenerate Fermi gas of about 7 × 104
173Yb atoms at T/T
F
=0.8(1), where T
F
is the Fermi temperature of the gas. We highlight the high performance of the Zeeman slower and the home-made frequency-doubling systems for 399-nm and 556-nm lasers.
Tài liệu tham khảo
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