Probing the backscattering of TiO2particles with vortex beams

Xavier Zambrana-Puyalto, Xavier Vidal, Gabriel Molina-Terriza

    Research output: Chapter in Book/Report/Conference proceedingConference proceeding contributionpeer-review

    34 Downloads (Pure)


    We present a set of experiments in which the backscattering spectra of 4 μm single TiO2 particles are probed with circularly polarized vortex beams. The experiment is carried out with a tunable laser at λ = 760 - 810nm. We observe that the use of vortex beams enables us to tailor the backscattering in different ways. Given a certain backscattering of a particle (induced by a Gaussian beam or a plane wave), we observe that vortex beams can tune it and sharpen it. Moreover, we also observe that the level of conservation of helicty can be increased thanks to the use of vortex beams. We explain the mechanisms that give rise to these effects using Mie Theory. Our method of backscattering control can be experimentally implemented in most of microscopy set-ups. In addition, if brought to its limits, the method can be used to excite single multipolar modes from spheres. We believe that our method could find application in the levitation of particles or the excitation of whispering gallery modes.

    Original languageEnglish
    Title of host publicationNanophotonics VIII
    EditorsDavid L. Andrews, Angus J. Bain, Martti Kauranen, Jean-Michel Nunzi
    Place of PublicationBellingham, Washington
    Number of pages9
    ISBN (Electronic)9781510634633
    ISBN (Print)9781510634626
    Publication statusPublished - 2020
    EventNanophotonics VIII 2020 - Virtual, Online, France
    Duration: 6 Apr 202010 Apr 2020

    Publication series

    NameProceedings of SPIE
    ISSN (Print)0277-786X
    ISSN (Electronic)1996-756X


    ConferenceNanophotonics VIII 2020
    CityVirtual, Online

    Bibliographical note

    Copyright 2020 Society of Photo-Optical Instrumentation Engineers (SPIE). One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper are prohibited.


    • Angular momentum
    • Helicity
    • Mie Theory
    • Multipoles
    • Phase singularity
    • Vortex beams
    • Whispering gallery modes


    Dive into the research topics of 'Probing the backscattering of TiO2particles with vortex beams'. Together they form a unique fingerprint.

    Cite this