# Resolved Sideband Cooling of a Levitated Nanoparticle in the Presence of Laser Phase Noise

## TL;DR

This paper explores how laser phase noise impacts resolved sideband cooling of levitated nanoparticles, identifying phase noise as a key obstacle and proposing strategies to achieve motional ground state cooling.

## Contribution

It investigates the role of laser phase noise in limiting cooling efficiency and suggests methods to overcome this obstacle for ground state cooling of levitated nanoparticles.

## Key findings

- Achieved minimal temperatures of 10 mK limited by phase noise
- Identified phase noise as the main obstacle in reaching motional ground state
- Proposed strategies for ground state cooling despite phase noise

## Abstract

We investigate the influence of laser phase noise heating on resolved sideband cooling in the context of cooling the center-of-mass motion of a levitated nanoparticle in a high-finesse cavity. Although phase noise heating is not a fundamental physical constraint, the regime where it becomes the main limitation in Levitodynamics has so far been unexplored and hence embodies from this point forward the main obstacle in reaching the motional ground state of levitated mesoscopic objects with resolved sideband cooling. We reach minimal center-of-mass temperatures comparable to $T_{min}=10$mK at a pressure of $p = 3\times 10^{-7}$mbar, solely limited by phase noise. Finally we present possible strategies towards motional ground state cooling in the presence of phase noise.