Print Email Facebook Twitter Ultrafast Time Dynamics of Plasmonic Fractional Orbital Angular Momentum Title Ultrafast Time Dynamics of Plasmonic Fractional Orbital Angular Momentum Author Bauer, T.A. (TU Delft QN/Kuipers Lab; Kavli institute of nanoscience Delft) Davis, Timothy J. (University of Stuttgart; Universität Duisburg-Essen; University of Melbourne) Frank, Bettina (University of Stuttgart) Dreher, Pascal (Universität Duisburg-Essen) Janoschka, David (Universität Duisburg-Essen) Meiler, Tim C. (University of Stuttgart) Meyer zu Heringdorf, Frank J. (Universität Duisburg-Essen) Kuipers, L. (TU Delft QN/Quantum Nanoscience; Kavli institute of nanoscience Delft) Giessen, Harald (University of Stuttgart) Department QN/Quantum Nanoscience Date 2023 Abstract The creation and manipulation of optical vortices, both in free space and in two-dimensional systems such as surface plasmon polaritons (SPPs), has attracted widespread attention in nano-optics due to their robust topological structure. Coupled with strong spatial confinement in the case of SPPs, these plasmonic vortices and their underlying orbital angular momentum (OAM) have promise in novel light-matter interactions on the nanoscale with applications ranging from on-chip particle manipulation to tailored control of plasmonic quasiparticles. Until now, predominantly integer OAM values have been investigated. Here, we measure and analyze the time evolution of fractional OAM SPPs using time-resolved two-photon photoemission electron microscopy and near-field optical microscopy. We experimentally show the field’s complex rotational dynamics and observe the beating of integer OAM eigenmodes at fractional OAM excitations. With our ability to access the ultrafast time dynamics of the electric field, we can follow the buildup of the plasmonic fractional OAM during the interference of the converging surface plasmons. By adiabatically increasing the phase discontinuity at the excitation boundary, we track the total OAM, leading to plateaus around integer OAM values that arise from the interplay between intrinsic and extrinsic OAM. Subject fractional orbital angular momentumnear-field scanning optical microscopyphotoemission electron microscopyplasmonic angular momentumtime-dynamics of 2D vortices To reference this document use: http://resolver.tudelft.nl/uuid:e1f10850-ea28-42a6-8997-8ba4e5c14b52 DOI https://doi.org/10.1021/acsphotonics.3c01036 ISSN 2330-4022 Source ACS Photonics, 10 (12), 4252-4258 Part of collection Institutional Repository Document type journal article Rights © 2023 T.A. Bauer, Timothy J. Davis, Bettina Frank, Pascal Dreher, David Janoschka, Tim C. Meiler, Frank J. Meyer zu Heringdorf, L. Kuipers, Harald Giessen Files PDF bauer_et_al_2023_ultrafas ... mentum.pdf 5.64 MB Close viewer /islandora/object/uuid:e1f10850-ea28-42a6-8997-8ba4e5c14b52/datastream/OBJ/view