Symmetry breaking in individual plasmonic nanoparticles
- Hui Wang*,†,
- Yanpeng Wu†,‡,
- Britt Lassiter†,‡,
- Colleen L. Nehl†,‡,
- Jason H. Hafner*,†,‡,
- Peter Nordlander†,‡,§, and
- Naomi J. Halas*,†,§,¶
- Departments of *Chemistry,
- ‡Physics and Astronomy, and
- §Electrical and Computer Engineering and
- †Laboratory for Nanophotonics, Rice University, Houston, TX 77005
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Communicated by James L. Kinsey, Rice University, Houston, TX, May 16, 2006 (received for review March 20, 2006)
Abstract
The plasmon resonances of a concentric metallic nanoshell arise from the hybridization of primitive plasmon modes of the same angular momentum on its inner and outer surfaces. For a nanoshell with an offset core, the reduction in symmetry relaxes these selection rules, allowing for an admixture of dipolar components in all plasmon modes of the particle. This metallodielectric nanostructure with reduced symmetry exhibits a core offset-dependent multipeaked spectrum, seen in single-particle spectroscopic measurements, and exhibits significantly larger local-field enhancements on its external surface than the equivalent concentric spherical nanostructure.
Footnotes
- ¶To whom correspondence should be addressed. E-mail: halas{at}rice.edu
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Author contributions: H.W., P.N., and N.J.H. designed research; H.W., Y.W., and B.L. performed research; B.L., C.L.N., and J.H.H. contributed new reagents/analytic tools; H.W., Y.W., J.H.H., P.N., and N.J.H. analyzed data; and H.W., P.N., and N.J.H. wrote the paper.
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Conflict of interest statement: No conflicts declared.
- Abbreviations:
- FDTD,
- finite difference time domain;
- NIR,
- near-infrared;
- TEM,
- transmission electron microcopy;
- PVP,
- poly(4-vinylpyridine).
Abbreviations:
- © 2006 by The National Academy of Sciences of the USA
