Probing optical anapoles with fast electron beams
Artikel i vetenskaplig tidskrift, 2023
Optical anapoles are intriguing charge-current distributions characterized by a strong suppression of electromagnetic radiation. They originate from the destructive interference of the radiation produced by electric and toroidal multipoles. Although anapoles in dielectric structures have been probed and mapped with a combination of near- and far-field optical techniques, their excitation using fast electron beams has not been explored so far. Here, we theoretically and experimentally analyze the excitation of optical anapoles in tungsten disulfide (WS2) nanodisks using Electron Energy Loss Spectroscopy (EELS) in Scanning Transmission Electron Microscopy (STEM). We observe prominent dips in the electron energy loss spectra and associate them with the excitation of optical anapoles and anapole-exciton hybrids. We are able to map the anapoles excited in the WS2 nanodisks with subnanometer resolution and find that their excitation can be controlled by placing the electron beam at different positions on the nanodisk. Considering current research on the anapole phenomenon, we envision EELS in STEM to become a useful tool for accessing optical anapoles appearing in a variety of dielectric nanoresonators.
Författare
Carlos Maciel-Escudero
CIC nanoGUNE
Consejo Superior de Investigaciones Científicas (CSIC)
Andrew Yankovich
Chalmers, Fysik, Nano- och biofysik
Battulga Munkhbat
Danmarks Tekniske Universitet (DTU)
Chalmers, Fysik, Nano- och biofysik
Denis Baranov
Chalmers, Fysik, Nano- och biofysik
Moscow Institute of Physics and Technology
Rainer Hillenbrand
CIC nanoGUNE
Basque Foundation for Science (Ikerbasque)
Eva Olsson
Chalmers, Fysik, Nano- och biofysik
Javier Aizpurua
Consejo Superior de Investigaciones Científicas (CSIC)
Donostia International Physics Center
Timur Shegai
Chalmers, Fysik, Nano- och biofysik
Nature Communications
2041-1723 (ISSN) 20411723 (eISSN)
Vol. 14 1 8478Kvantplasmonik – en teknologi för foton-fotonväxelverkan på kvantnivå vid rumstemperatur
Vetenskapsrådet (VR) (2016-06059), 2017-01-01 -- 2022-12-31.
Plasmon-exciton coupling at the attosecond-subnanometer scale: Tailoring strong light-matter interactions at room temperature
Knut och Alice Wallenbergs Stiftelse (2019.0140), 2020-07-01 -- 2025-06-30.
Ämneskategorier (SSIF 2011)
Beräkningsmatematik
Astronomi, astrofysik och kosmologi
Atom- och molekylfysik och optik
Annan fysik
Den kondenserade materiens fysik
DOI
10.1038/s41467-023-43813-y
PubMed
38123545