3D sympathetic cooling and detection of levitated nanoparticles

TL;DR

This paper demonstrates three-dimensional sympathetic cooling and detection of levitated nanoparticles using a Paul trap, enabling control of particles that are difficult to cool with laser light, advancing quantum experiments at mesoscopic scales.

Contribution

It introduces a method for sympathetically cooling and detecting levitated nanoparticles in three dimensions within a Paul trap, including identification of two cooling regimes.

Findings

Sympathetically cooled particles thermalize with directly cooled ones.

Minimum achievable temperature for sympathetically cooled particles.

Potential for controlling arrays of trapped nanoparticles.

Abstract

Cooling the center-of-mass motion of levitated nanoparticles provides a route to quantum experiments at mesoscopic scales. Here we demonstrate three-dimensional sympathetic cooling and detection of the center-of-mass motion of a levitated silica nanoparticle. The nanoparticle is electrostatically coupled to a feedback-cooled particle while both particles are trapped in the same Paul trap. We identify two regimes, based on the strength of the cooling: in the first regime, the sympathetically cooled particle thermalizes with the directly cooled one, while in the second regime, the sympathetically cooled particle reaches a minimum temperature. This result provides a route to efficiently cool and detect particles that cannot be illuminated with strong laser light, such as absorptive particles, and paves the way for controlling the motion of arrays of several trapped nanoparticles.