An efficient magneto-optical trap of metastable krypton atoms

We report a magneto-optical trap of metastable krypton atoms with a trap loading rate of [12pt]{minimal}{document}3× 10¹¹{document}3×1011 atoms/s and a trap capture efficiency of [12pt]{minimal}{document}3× 10⁻⁵{document}3×10−5. The system starts with an atomic beam of metastable krypton produced in a liquid-nitrogen cooled, radio-frequency driven discharge. The metastable beam flux emerging from the discharge is [12pt]{minimal}{document}1.5× 10¹⁴{document}1.5×1014 atoms/s/sr. The flux in the forward direction is enhanced by a factor of 156 with transverse laser cooling. The atoms are then slowed inside a Zeeman slower before captured by a magneto-optic trap. The trap efficiency can be further improved, possibly to the [12pt]{minimal}{document}10⁻²{document}10−2 level, by gas recirculation. Such an atom trap is useful in trace analysis applications where available sample size is limited.