Final Report Summary - QMES (Quantum Mesoscopics with Vacuum Trapped Nanoparticles)
The objective of this project is to optically trap a dielectric nanoparticle in ultrahigh vacuum and to bring its center-of-mass motion to rest by means of feedback control. Quantum mechanics predicts that the particle has a finite zero-point energy and the goal of our work was to demonstrate that a macroscopic object like the nanoparticle can be brought close to this quantum ground state. Using active feedback control we have succeeded in cooling the particle to temperatures that are equivalent to four energy quanta. Using heterodyne interferometry we have experimentally measured the Raman sideband asymmetry, which unambiguously proves that the particle has been transitioned into the quantum regime. This result paves the way for macroscopic quantum physics, such as macroscopic superposition states and the interplay between quantum mechanics and gravity.