Dual Magneto-Optical Trap of Sodium Atoms in Ground Hyperfine $F=1$ and $F=2$ States

Sodium atoms were trapped in a dual-operation magneto-optical trap using laser light whose frequency was tuned at 18 MHz to the red of the F=2 to F'=3 transition and laser light whose frequency was tuned at 11 MHz to the red of the F=1 to F'=0 transition. The number of trapped atoms increased to 1.2×1010 atoms, which is a sufficient number for producing the Bose–Einstein condensation of a dilute sodium gas. The mechanism for trapping atoms in the F=1 state is discussed.