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arXiv · 1701.04814

Measurements of trapped-ion heating rates with exchangeable surfaces in close proximity

Abstract

Electric-field noise from the surfaces of ion-trap electrodes couples to the ion's charge causing heating of the ion's motional modes. This heating limits the fidelity of quantum gates implemented in quantum information processing experiments. The exact mechanism that gives rise to electric-field noise from surfaces is not well-understood and remains an active area of research. In this work, we detail experiments intended to measure ion motional heating rates with exchangeable surfaces positioned in close proximity to the ion, as a sensor to electric-field noise. We have prepared samples with various surface conditions, characterized in situ with scanned probe microscopy and electron spectroscopy, ranging in degrees of cleanliness and structural order. The heating-rate data, however, show no significant differences between the disparate surfaces that were probed. These results suggest that the driving mechanism for electric-field noise from surfaces is due to more than just thermal excitations alone.

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D. A. Hite, K. S. McKay, S. Kotler, D. Leibfried, D. J. Wineland, D. P. Pappas. 2017-01-17. Measurements of trapped-ion heating rates with exchangeable surfaces in close proximity. https://doi.org/10.1557/adv.2017.14

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