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Magnetic-plasmonic core-shell nanoparticles.

ABSTRACT: Nanoparticles composed of magnetic cores with continuous Au shell layers simultaneously possess both magnetic and plasmonic properties. Faceted and tetracubic nanocrystals consisting of wustite with magnetite-rich corners and edges retain magnetic properties when coated with a Au shell layer, with the composite nanostructures showing ferrimagnetic behavior. The plasmonic properties are profoundly influenced by the high dielectric constant of the mixed iron oxide nanocrystalline core. A comprehensive theoretical analysis that examines the geometric plasmon tunability over a range of core permittivities enables us to identify the dielectric properties of the mixed oxide magnetic core directly from the plasmonic behavior of the core-shell nanoparticle.

SUBMITTER: Levin CS

PROVIDER: S-EPMC4108303 | biostudies-literature | 2009 Jun

REPOSITORIES: biostudies-literature

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Magnetic-plasmonic core-shell nanoparticles.

Levin Carly S CS Hofmann Cristina C Ali Tamer A TA Kelly Anna T AT Morosan Emilia E Nordlander Peter P Whitmire Kenton H KH Halas Naomi J NJ

ACS nano 20090601 6

Nanoparticles composed of magnetic cores with continuous Au shell layers simultaneously possess both magnetic and plasmonic properties. Faceted and tetracubic nanocrystals consisting of wustite with magnetite-rich corners and edges retain magnetic properties when coated with a Au shell layer, with the composite nanostructures showing ferrimagnetic behavior. The plasmonic properties are profoundly influenced by the high dielectric constant of the mixed iron oxide nanocrystalline core. A comprehen ...[more]

PMID: 19441794

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