Fast Ground State Manipulation of Neutral Atoms in Microscopic Optical Traps

Abstract

We demonstrate Rabi flopping at MHz rates between ground hyperfine states of neutral ${}^{87}\mathrm{Rb}$ atoms that are trapped in two micron sized optical traps. Using tightly focused laser beams we demonstrate high fidelity, site specific Rabi rotations with cross talk on neighboring sites separated by $8\mu \mathrm{m}$ at the level of ${10}^{-3}$. Ramsey spectroscopy is used to measure a dephasing time of $870\mu \mathrm{s}$, which is $\approx 5000\mathrm{\text{times}}$ longer than the time for a $\pi /2$ pulse.