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arXiv · 1804.01952

Phase-space study of surface-electrode Paul traps: Integrable, chaotic, and mixed motions

V. Roberdel·D. Leibfried·D. Ullmo·H. Landa
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Abstract

We present a comprehensive phase-space treatment of the motion of charged particles in electrodynamic traps. Focusing on five-wire surface-electrode Paul traps, we study the details of integrable and chaotic motion of a single ion. We introduce appropriate phase-space measures and give a universal characterization of the trap effectiveness as a function of the parameters. We rigorously derive the commonly used (time-independent) pseudopotential approximation, quantify its regime of validity and analyze the mechanism of its breakdown within the time-dependent potential. The phase space approach that we develop gives a general framework for describing ion dynamics in a broad variety of surface Paul traps. To probe this framework experimentally, we propose and analyze, using numerical simulations, an experiment that can be realized with an existing four-wire trap. We predict a robust experimental signature of the existence of trapping pockets within a mixed regular and chaotic phase-space structure. Intricately rich escape dynamics suggest that surface traps give access to exploring microscopic Hamiltonian transport phenomena in phase space.

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V. Roberdel, D. Leibfried, D. Ullmo, H. Landa. 2018-04-05. Phase-space study of surface-electrode Paul traps: Integrable, chaotic, and mixed motions. https://doi.org/10.1103/physreva.97.053419

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