  We study the suppression of noise-induced phase decoherence in a single
atomic qubit by employing pulse sequences. The atomic qubit is composed of a
single neutral atom in a far-detuned optical dipole trap and the phase
decoherence may originate from the laser intensity and beam pointing
fluctuations as well as magnetic field fluctuations. We show that suitable
pulse sequences may prolongate the qubit coherence time substantially as
comparing to the conventional spin echo pulse.
