STEEP MAGNETIC TRAP FOR ULTRA-COLD ATOMS

A combination of current coils and ferromagnetic pole shoes is used to construct a magnetic quadrupole trap for ultra cold neutral atoms. Fi eld gradients of up to 3000 G/cm have been achieved continuously with an electric power consumption of only 10 watts. A maximum field gradie nt of 1 T/cm is calculated for a current that can be applied for sever al seconds. The trap has been loaded with 8 x 10(6) lithium atoms (Li- 7) from a magneto-optical trap and the energy distribution determined by stepwise reduction of the trapping potential. Finally, magnetic tra pping of fermionic Li-6 has been demonstrated.