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arXiv · 1507.05207

Phase-stable free-space optical lattices for trapped ions

Christian Tomas Schmiegelow·Henning Kaufmann·Thomas Ruster·Jonas Schulz·Vidyut Kaushal·Max Hettrich·Ferdinand Schmidt-Kaler·Ulrich G. Poschinger
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Abstract

We demonstrate control of the absolute phase of an optical lattice with respect to a single trapped ion. The lattice is generated by off-resonant free-space laser beams, we actively stabilize its phase by measuring its ac-Stark shift on a trapped ion. The ion is localized within the standing wave to better than 2\% of its period. The locked lattice allows us to apply displacement operations via resonant optical forces with a controlled direction in phase space. Moreover, we observe the lattice-induced phase evolution of spin superposition states in order to analyze the relevant decoherence mechanisms. Finally, we employ lattice-induced phase shifts for inferring the variation of the ion position over 157~$\mu$m range along the trap axis at accuracies of better than 6~nm.

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Christian Tomas Schmiegelow, Henning Kaufmann, Thomas Ruster, Jonas Schulz, Vidyut Kaushal, Max Hettrich, Ferdinand Schmidt-Kaler, Ulrich G. Poschinger. 2015-07-18. Phase-stable free-space optical lattices for trapped ions. https://doi.org/10.1103/physrevlett.116.033002

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