Symmetry breaking in linear multipole traps

Abstract

Radiofrequency multipole traps have been used for some decades in cold collision experiments and are gaining interest for precision spectroscopy due to their low micromotion contribution and the predicted unusual cold-ion structures. However, the experimental realisation is not yet fully controlled, and open questions in the operation of these devices remain. We present experimental observations of symmetry breaking of the trapping potential in a macroscopic octupole trap with laser-cooled ions. Numerical simulations have been performed in order to explain the appearance of additional local potential minima and be able to control them in a next step. We characterise these additional potential minima, in particular with respect to their position, their potential depth and their probability of population as a function of the radial and angular displacement of the trapping rods.

Keywords:

• Radiofrequency multipole traps
• laser cooling
• symmetry-breaking
• micro-motion

Acknowledgements

M.R.K. acknowledges financial support from CNES and Région Provence-Alpes-Côte d’Azur.

Notes

No potential conflict of interest was reported by the authors.

This article was originally published with errors. This version has been corrected. Please see Erratum (https://doi.org/10.1080/09500340.2018.1427315)

Additional information

Funding

This work has been financially supported by ANR [grant number ANR-08-JCJC-0053-01], CNES [contract number 116279], [contract number 151084], and Région PACA.