Direct and clean loading of nanoparticles into optical traps at millibar pressures

TL;DR

This paper introduces a novel dry, clean method using Laser Induced Acoustic Desorption for directly loading nanoparticles into optical traps at low pressures, avoiding liquid contamination and enabling efficient trapping.

Contribution

The authors demonstrate a new technique for loading nanoparticles into optical traps at millibar pressures without liquids, improving cleanliness and efficiency over previous methods.

Findings

Successful trapping at pressures down to 1 mbar

Compatible with site-selective loading of nanofabricated particles

Provides a rapid and efficient trapping process

Abstract

Nanoparticles levitated by optical fields under vacuum conditions have applications in quantum science, the study of nanothermodynamics and precision sensing. Existing techniques for loading optical traps require ambient conditions, and often involve dispersion in liquids, which can contaminate delicate optics and lead to enhanced optical absorption and heating. Here we present a clean, dry and generic mechanism for directly loading optical traps at pressures down to 1\,mbar, exploiting Laser Induced Acoustic Desorption. Our method allows rapid and efficient trapping, and is also suitable for site-selective loading of nanofabricated particles grown on a silicon substrate.