Measuring the Internal Temperature of a Levitated Nanoparticle in High Vacuum

TL;DR

This paper demonstrates a method to determine the internal temperature of a levitated nanoparticle in high vacuum by analyzing its center-of-mass motion, revealing an internal temperature of approximately 1000 K, which impacts quantum coherence.

Contribution

It introduces a novel approach to measure the internal temperature of levitated nanoparticles through their center-of-mass dynamics, linking thermal properties to quantum state coherence.

Findings

Internal temperature of nanoparticle measured at ~1000 K

Coupling between internal degrees of freedom and motion analyzed

Implications for quantum coherence limits in nanomechanical systems

Abstract

The interaction of an object with its surrounding bath can lead to a coupling between the object's internal degrees of freedom and its center-of-mass motion. This coupling is especially important for nanomechanical oscillators, which are amongst the most promising systems for preparing macroscopic objects in quantum mechanical states. Here we exploit this coupling to derive the internal temperature of a levitated nanoparticle from measurements of its center-of-mass dynamics. For a laser-trapped silica particle in high vacuum we find an internal temperature of $1000(60)\,\mathrm{K}$. The measurement and control of the internal temperature of nanomechanical oscillators is of fundamental importance because blackbody emission sets limits to the coherence of macroscopic quantum states.