Characterization of a surface electrode Paul trap for frequency metrology

Josipa Madunic, Moustafa Abdel Hafiz, Y. Kersalé, Clément Lacroûte

Published May 15, 2023• 0 citations

Abstract

We report on the progress on a single-ion optical clock that is being developed at the FEMTO-ST institute. Our objective is to reach a fractional frequency stability of the order of 10-14 at one second for a total volume well below 500 L. The experimental setup is based on a surface electrode single-ion trap. A new trapping chip was designed and produced at the local cleanroom facility, using deep reactive-ion etching (DRIE) on a silicon on insulator- (SOI) wafer. Paul traps require a source of highly-stable and low noise voltage in the radio-frequency (RF) domain. A resonator of our own design has been used to supply high voltage to the trap. We have developed and implemented techniques for 3D micromotion reduction in order to minimize the 2nd order Doppler shift. Indeed, for Yb+ optical spectroscopy, second order Doppler shift and Stark shift due to the ac fields can contribute significantly to the uncertainty budget. We will present the latest results of the trap characterization, which should include lifetime and heating rate measurements of the trap.

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