  An array of single Rydberg atoms driven by a frequency modulated light field
is studied. The periodic modulation effectively modifies the Rabi coupling,
leading to unprecedented dynamics in the presence of Rydberg-Rydberg
interactions. They include state dependent population trapping, the Rydberg
blockade for small and anti-blockades at large interaction strengths.
Interestingly, the Schrieffer-wolf transformation reveals a fundamental process
in Rydberg gases, correlated Rabi oscillations, arising from the long-range
interactions, provides an alternative depiction for Rydberg blockade and it
exhibits a nontrivial behaviour in the presence of periodic modulation. The
dynamical localization of a many body configuration in a driven Rydberg-lattice
is discussed.
