We have magneto-optically trapped the nine stable isotopes of xenon. Using the Zeeman slowing method to decelerate a beam of xenon atoms in the metastable 6s 3/2 [3/2
]2 state (notation representing nl
Jcore [K=
Jcore+l
]J), we load our trap to a collisionally limited density of more than
1010 atoms/
cm3. The two odd isotopes are trapped without a repumping frequency, even though they have hyperfine structure. The sensitivity of the trapping process to the laser frequency is exploited to make accurate measurements of the isotope shifts for the 6s 3/2 [3/2
]2\ensuremath{\rightarrow}6p 3/2 [5/2
]3 laser-cooling transition and of the hyperfine constants for
131Xe.
A system for three-photon Doppler-free excitation of two-level atoms is proposed. It is shown that this is equivalent to the excitation of a two-level system with an effective interaction Hamiltonian. An analysis is made of a system for selecting the detuning of the excitation frequencies that can completely compensate for Doppler broadening. Numerical estimates are made and these show that even for small isotope shifts and high temperatures of the excited gas, excitation having a high probability and a high isotopic selectivity can be achieved.