  We investigate single cesium (Cs) atom heating owing to the momentum
accumulation process induced by the resonant pulsed excitation in a microscopic
optical dipole trap formed by a strongly focused 1064 nm laser beam. The
heating depends on the trap frequency which restricts the maximum repetition
rate of pulsed excitation. We experimentally verify the heating of a single
atom and then demonstrate how to suppress it with an optimized pulsed
excitation/cooling method. The typical trap lifetime of single Cs atom is
extended from 108 +/- 6 us to 2536 +/- 31 ms, and the corresponding number of
excitation increases from ~ 108 to ~ 360000. In applying this faster cooling
method, we use the trapped single Cs atom as a triggered single-photon source
at an excitation repetition rate of 10 MHz. The second-order intensity
correlations of the emitted single photons are characterized by implementing
Hanbury Brown and Twiss setup, and clear anti-bunching effect has been
observed.
