Surface- and tip-enhanced Raman spectroscopy reveals spin-waves in iron oxide nanoparticles

Nanomaterials have the remarkable characteristic of displaying physical properties different from their bulk counterparts. An additional degree of complexity and functionality arises when oxide nanoparticles interact with metallic nanostructures. In this context the Raman spectra due to plasmonic enhancement of iron oxide nanocrystals are here reported showing the activation of spin-waves. Iron oxide nanoparticles on gold and silver tips are found to display a band around 1584 cm−1 attributed to a spin-wave magnon mode. This magnon mode is not observed for nanoparticles deposited on silicon (111) or on glass substrates. Metal–nanoparticle interaction and the strongly localized electromagnetic field contribute to the appearance of this mode. The localized excitation that generates this mode is confirmed by tip-enhanced Raman spectroscopy (TERS). The appearance of the spin-waves only when the TERS tip is in close proximity to a nanocrystal edge suggests that the coupling of a localized plasmon with spin-waves arises due to broken symmetry at the nanoparticle border and the additional electric field confinement. Beyond phonon confinement effects previously reported in similar systems, this work offers significant insights on the plasmon-assisted generation and detection of spin-waves optically induced. / Dieser Beitrag ist aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.

Identiferoai:union.ndltd.org:DRESDEN/oai:qucosa:de:qucosa:20249
Date03 June 2015
CreatorsRodriguez, Raul D., Sheremet, Evgeniya, Deckert-Gaudig, Tanja, Chaneac, Corinne, Hietschold, Michael, Deckert, Volker, Zahn, Dietrich R. T.
ContributorsRoyal Society of Chemistry
PublisherTechnische Universität Chemnitz
Source SetsHochschulschriftenserver (HSSS) der SLUB Dresden
LanguageEnglish
Detected LanguageEnglish
Typedoc-type:article, info:eu-repo/semantics/article, doc-type:Text
SourceNanoscale, 2015
Rightsinfo:eu-repo/semantics/openAccess
Relation10.1039/C5NR01277E, 2040-3372

Page generated in 0.0024 seconds