Squeezed light from a levitated nanoparticle at room temperature

TL;DR

This paper demonstrates room-temperature optical squeezing from a levitated nanoparticle without using an optical cavity, achieving noise reduction and opening new avenues for sensing and entanglement in quantum optomechanics.

Contribution

It introduces a cavity-less method for generating squeezed light from a levitated nanoparticle at room temperature, simplifying experimental requirements.

Findings

Achieved 9% noise reduction below shot noise.

Used heterodyne detection for quadrature reconstruction.

Presented a new platform for quantum sensing and entanglement studies.

Abstract

Quantum measurements of mechanical systems can produce optical squeezing via ponderomotive forces. Its observation requires high environmental isolation and efficient detection, typically achieved by using optical cavities and cryogenic cooling. Here we realize these conditions by measuring the position of an optically levitated nanoparticle at room temperature and without the overhead of an optical cavity. We use a fast heterodyne detection to reconstruct simultaneously orthogonal optical quadratures, and observe a noise reduction of $9\%\pm0.5\%$ below shot noise. Our experiment offers a novel, cavity-less platform for squeezed-light enhanced sensing. At the same time it delineates a clear and simple strategy towards observation of stationary optomechanical entanglement.