Fast Ground State Manipulation of Neutral Atoms in Microscopic Optical   Traps
  We demonstrate Rabi flopping at MHz rates between ground hyperfine states of neutral $^{87}$Rb atoms that are trapped in two micron sized optical traps. Using tightly focused laser beams we demonstrate high fidelity, site specific Rabi rotations with crosstalk on neighboring sites separated by $8 \mu\rm m$ at the level of $10^{-3}$. Ramsey spectroscopy is used to measure a dephasing time of $870 \mu\rm s$ which is $\approx$ 5000 times longer than the time for a $\pi/2$ pulse. 
D. D. Yavuz, P. B. Kulatunga, E. Urban, T. A. Johnson, N. Proite, T.   Henage, T.G. Walker, and M. Saffman