Thompson, Jeffrey DouglasTiecke, TobiasZibrov, AlexanderVuletić, V.Lukin, Mikhail2014-07-282013Thompson, J., T. Tiecke, A. Zibrov, V. Vuletić, and M. Lukin. 2013. Coherence and Raman Sideband Cooling of a Single Atom in an Optical Tweezer. Physical Review Letters 110(13): 133001.0031-9007http://nrs.harvard.edu/urn-3:HUL.InstRepos:12563779We investigate quantum control of a single atom in a tightly focused optical tweezer trap. We show that inevitable spatially varying polarization gives rise to significant internal-state decoherence but that this effect can be mitigated by an appropriately chosen magnetic bias field. This enables Raman sideband cooling of a single atom close to its three-dimensional ground state (vibrational quantum numbers \(\bar n_x=\bar n_y=0.01, \bar n_z=8)\) even for a trap beam waist as small as \(\omega=900  nm\). The small atomic wave packet with \(\delta x=\delta y=24  nm\) and \(\delta z=270  nm\) represents a promising starting point for future hybrid quantum systems where atoms are placed in close proximity to surfaces.en-USJournal Article2014-07-2810.1103/PhysRevLett.110.133001