Measurement of the Coulomb Logarithm in a Radio-Frequency Paul Trap

TL;DR

This paper reports a direct measurement of the Coulomb logarithm in a linear Paul trap by analyzing the heating of ultracold Yb+ ions, providing insights into ion cloud thermodynamics and implications for quantum information processing.

Contribution

It introduces a method to measure the Coulomb logarithm in a Paul trap using ion heating dynamics, enhancing understanding of ion interactions and thermodynamics.

Findings

Direct measurement of the Coulomb logarithm in a Paul trap.

Validation of a theoretical model for ion-ion heating.

Implications for improving trapped-ion quantum computing.

Abstract

Samples of ultracold 174 Yb+ ions, confined in a linear radio-frequency Paul trap, are heated via self-induced micromotion interruption, while their temperature, density, and therefore structural phase are monitored and simulated. The observed time evolution of the ion temperature is compared to a theoretical model for ion-ion heating allowing a direct measurement of the Coulomb logarithm in a linear Paul trap. This result permits a simple, yet accurate, analytical description of ion cloud thermodynamic properties, e.g. density, temperature, and structural phase, as well as suggests limits to and improvements for on-going trapped-ion quantum information efforts.