Show simple item record

dc.contributor.advisor Halas, Naomi J.
dc.creatorLal, Surbhi
dc.date.accessioned 2009-06-04T06:49:33Z
dc.date.available 2009-06-04T06:49:33Z
dc.date.issued 2006
dc.identifier.urihttp://hdl.handle.net/1911/18932
dc.description.abstract Plasmon resonances in metal nanoparticles control the far field and near field optical properties of these metallic structures. The enhanced electromagnetic near field is strongest at the surface of the nanoparticles and rapidly decays away from the surface. This enhanced near field is exploited in surface enhanced spectroscopies including Surface Enhanced Raman Spectroscopy (SERS) and Metal Enhanced Fluorescence Spectroscopy (MEFS). A measurement of the decay profile of the fringing field is important both for further development of surface enhanced spectroscopy for sensor device application, and for understanding from a fundamental physics point of view. Gold nanoshells are spherical colloidal nanoparticles with a silica core covered by a thin gold shell. The plasmon resonance of nanoshells can be controllably tuned in the visible and infrared parts of the spectrum. The near field profile of nanoshells can be theoretically calculated on the basis of Mie scattering theory. The thesis describes a series of experiments designed to experimentally verify the near field profile of nanoshells. A scaffold of ss-DNA is used to place a fluorescein dye molecule at varying distances from the nanoshell surface. The SERS intensity from both the scaffold molecules and the fluorescein placed at the end of the tether is measured simultaneously and self consistently. The fluorescein-ss-DNA nanoshell conjugate structures are also used to study the distance dependence of the fluorescence emission from fluorescein. The thesis discusses the results of the SERS intensity profile agreement with the intensity profile calculated using Mie scattering theory. The quenching and enhancement of the fluorescence emission at varying distances from the nanoshell surface are also discussed.
dc.format.extent 76 p.
dc.format.mimetype application/pdf
dc.language.iso eng
dc.subjectAnalytical chemistry
Optics
dc.title Profiling the near field of nanoshells using surface enhanced Raman spectroscopy and fluorescence spectroscopy
dc.type.genre Thesis
dc.type.material Text
thesis.degree.department Chemistry
thesis.degree.discipline Natural Sciences
thesis.degree.grantor Rice University
thesis.degree.level Doctoral
thesis.degree.name Doctor of Philosophy
dc.identifier.citation Lal, Surbhi. "Profiling the near field of nanoshells using surface enhanced Raman spectroscopy and fluorescence spectroscopy." (2006) PhD diss., Rice University. http://hdl.handle.net/1911/18932.


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record