2020/08/31 by Larissa Kohler, Matthias Mader, Christian Kern +2 · 28 citations
Engineering · Physics and Astronomy · #Brownian motion #Characterization (materials science) #Computer science #Finesse #Laser #Materials science #Microfluidics #Nanotechnology #Optics #Orbital Angular Momentum in Optics #Photonic Crystals and Applications #Photonic and Optical Devices #Photonics #Physics #Refractive index #Sprite (computer graphics) #physics.optics
paper · pdf · doi:10.1038/s41467-021-26719-5
published in Nature Communications 12(1), 6385 (Nature Portfolio) · 7 pages, 3 figures
arxiv created 2021/01/14 · openalex publication_date 2021/11/04 · arxiv updated 2022/01/05 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
Abstract The dynamics of nanosystems in solution contain a wealth of information with relevance for diverse fields ranging from materials science to biology and biomedical applications. When nanosystems are marked with fluorophores or strong scatterers, it is possible to track their position and reveal internal motion with high spatial and temporal resolution. However, markers can be toxic, expensive, or change the object’s intrinsic properties. Here, we simultaneously measure dispersive frequency shifts of three transverse modes of a high-finesse microcavity to obtain the three-dimensional path of unlabeled SiO 2 nanospheres with 300 μ s temporal and down to 8 nm spatial resolution. This allows us to quantitatively determine properties such as the polarizability, hydrodynamic radius, and effective refractive index. The fiber-based cavity is integrated in a direct-laser-written microfluidic device that enables the precise control of the fluid with ultra-small sample volumes. Our approach enables quantitative nanomaterial characterization and the analysis of biomolecular motion at high bandwidth.