Image-current mediated sympathetic laser cooling of a single proton in a Penning trap down to 170 mK axial temperature

TL;DR

This paper reports a significant advancement in cooling a single proton in a Penning trap to 170 mK using image-current mediated sympathetic cooling with laser-cooled beryllium ions, enabling improved precision in measurements.

Contribution

It introduces a novel cooling method that achieves a new temperature record for a single proton in a Penning trap, applicable to various charged particles.

Findings

Achieved 170 mK axial temperature for a proton

Demonstrated 15-fold improvement over previous cooling methods

Established a new benchmark for particle cooling in Penning traps

Abstract

We demonstrate a new temperature record for image-current mediated sympathetic cooling of a single proton in a cryogenic Penning trap by laser-cooled $^9$Be$^+$. An axial mode temperature of 170 mK is reached, which is a 15-fold improvement compared to the previous best value. Our cooling technique is applicable to any charged particle, so that the measurements presented here constitute a milestone towards the next generation of high-precision Penning-trap measurements with exotic particles.