Optomechanical Detection of Individual Gas Collisions

We experimentally demonstrate the detection of momentum transfers from individual collisions of Kr, Xe, and SF$_6$ with an optically levitated nanoparticle, finding good agreement with theoretical expectations. The observed event rates accurately measure the gas partial pressures, while the spectral shape provides a sensitive probe of the surface properties of the nanoparticle, including its temperature. The reconstruction of impulse signals as small as 200 keV/$c$ further establishes that levitated optomechanical sensors can reach the sensitivity required for precision measurements of fundamental particle interactions, and demonstrates a proof-of-principle for a primary pressure sensor based on the detection of individual gas particle collisions.

Source: arXiv:2604.18371v1 - http://arxiv.org/abs/2604.18371v1 PDF: https://arxiv.org/pdf/2604.18371v1 Original Link: http://arxiv.org/abs/2604.18371v1