Review of Scientific Instruments

Micro-fabricated stylus ion trap

Christian Lew Arrington, Kyle S. McKay, Ehren Donel Baca, Jonathan Joseph Coleman, Yves Colombe, Patrick Sean Finnegan, Dustin A. Hite, Andrew E Hollowell, Robert Jördens, John D. Jost, Dietrich G. Leibfried, Adam M. Rowen, Ulrich Warring, Martin P. Weides, A. C. Wilson, David J. Wineland, David P. Pappas

Published Aug 1, 2013• 25 citations

Publisher

Abstract

An electroformed, three-dimensional stylus Paul trap was designed to confine a single atomic ion for use as a sensor to probe the electric-field noise of proximate surfaces. The trap was microfabricated with the UV-LIGA technique to reduce the distance of the ion from the surface of interest. We detail the fabrication process used to produce a 150 μm tall stylus trap with feature sizes of 40 μm. We confined single, laser-cooled, (25)Mg(+) ions with lifetimes greater than 2 h above the stylus trap in an ultra-high-vacuum environment. After cooling a motional mode of the ion at 4 MHz close to its ground state (<n> = 0.34 ± 0.07), the heating rate of the trap was measured with Raman sideband spectroscopy to be 387 ± 15 quanta/s at an ion height of 62 μm above the stylus electrodes.

DOI: 10.1063/1.4817304

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