  Femtosecond time-resolved x-ray diffraction is employed to study the dynamics
of the periodic lattice distortion (PLD) associated with the
charge-density-wave (CDW) in K0.3MoO3. Using a multi-pulse scheme we show the
ability to extend the lifetime of coherent oscillations of the PLD about the
undistorted structure through re-excitation of the electronic states. This
suggests that it is possible to enter a regime where the symmetry of the
potential energy landscape corresponds to the high symmetry phase but the
scattering pathways that lead to the damping of coherent dynamics are still
controllable by altering the electronic state population. The demonstrated
control over the coherence time offers new routes for manipulation of coherent
lattice states.
