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arXiv · 2007.09422

Sub-ms, nondestructive, time-resolved quantum-state readout of a single, trapped neutral atom

Margaret E. Shea·Paul M. Baker·James A. Joseph·Jungsang Kim·Daniel J. Gauthier
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Abstract

We achieve fast, nondestructive quantum-state readout via fluorescence detection of a single $^{87}$Rb atom in the 5$S_{1/2}$ ($F=2$) ground state held in an optical dipole trap. The atom is driven by linearly-polarized readout laser beams, making the scheme insensitive to the distribution of atomic population in the magnetic sub-levels. We demonstrate a readout fidelity of $97.6\pm0.2\%$ in a readout time of $160\pm20$ $μ$s with the atom retained in $>97\%$ of the trials, representing an advancement over other magnetic-state-insensitive techniques. We demonstrate that the $F=2$ state is partially protected from optical pumping by the distribution of the dipole matrix elements for the various transitions and the AC-Stark shifts from the optical trap. Our results are likely to find application in neutral-atom quantum computing and simulation.

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Margaret E. Shea, Paul M. Baker, James A. Joseph, Jungsang Kim, Daniel J. Gauthier. 2020-10-11. Sub-ms, nondestructive, time-resolved quantum-state readout of a single, trapped neutral atom. https://doi.org/10.1103/physreva.102.053101

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