Code: FOB	Time Slot/Poster Number: 10:00 - 10:20 am	Session: SERS (substrate development, single molecule, theory) I
Engineered SERS Substrates with Multiscale Signal Enhancement: Nanoparticle Cluster Arrays
Bjoern Reinhard
Boston University, Boston, MA
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Summary
Nanoparticle Cluster Arrays (NCAs) are two-dimensional arrays of nanoparticle clusters with defined morphology. The optical response and the field enhancement generated by these photonic-plasmonic crystals can be tuned in a rational fashion through control of the cluster size and the intercluster separation. Electromagnetic interactions on inter- and intracluster length scales in NCAs result in a multiscale SERS signal enhancement.

Code: FOB	Time Slot/Poster Number: 10:20 - 10:40 am	Session: SERS (substrate development, single molecule, theory) II
SERRS Through Hybridized Exciton-Plasmon Polaritons in Nanostructured Silver Films
Nicholas Cade; Tom Ritman-Meer; David Richards
Department of Physics, King's College London, London, United Kingdom
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Summary
We report on the resonant coupling between localized surface plasmon resonances (LSPRs) in nanostructured Ag films and an adsorbed monolayer of Rhodamine 6G. Hybridization of the LSPRs and molecular excitons creates new coupled polaritonic modes, which have been tuned by varying the plasmon wavelength. The resulting polariton dispersion shows an anticrossing behavior which is well fit by a simple coupled-oscillator Hamiltonian, giving a giant Rabi-splitting of 400 meV. The Raman spectra of R6G on these films show a large SERS effect. In particular, we find a maximum signal for resonance with the polariton, rather than the bare plasmon or exciton.

Code: FOB	Time Slot/Poster Number: 08:30 - 09:00 am	Session: SERS (Substrates, Single Molecule, Theory) II
New Operation Mode for SERS Using Ultrathin-Silica-Shelled Gold Nanoparticles
Jian-Feng Li1; Zhi-Lin Yang1; Yi-Fan Huang1; Yong Ding2; De-Yin Wu1; Bin Ren1; Zhong Lin Wang2; Zhong-Qun Tian1
1State Key Lab. of Phys. Chem. of Solid Surfaces, Xiamen, China; 2Sch. of Mater. Sci. and Eng.,Georgia Inst. of Tech, Atlanta, USA
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Summary
SERS applications are generally restricted to ‘free-electron-like’ metal (such as Au, Ag and Cu) nanostructures. By changing the working mode from direct contact (SERS) or non-contact (TERS) to the shell-isolated mode for surface Raman spectroscopy by using ultrathin-silica-shelled gold nanoparticles, we have avoided the long-standing limitations (inaccessibility or difficulty) of SERS for the characterization of atomically flat surfaces of various materials. We name it as shelled-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS).

Code: FOB	Time Slot/Poster Number: 09:00 - 09:20 am	Session: SERS (Substrates, Single Molecule, Theory) II
Nanofabrication of Disc on Pillar Substrates for Surface Enhanced Raman Spectroscopy
Michael Sepaniak1; Deepak bhandari1; Sabrina Wells1; Nickolay Lavrik2
1University of Tennessee, Knoxville, TN; 2Oak Ridge National Labroatory, Oak Ridge, TN
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Summary
Electron beam lithography and reactive ion etching nanofabrication techniques can be used to create silicon pillar systems which, when metalized, serve as SERS substrates. We describe in this paper the creation of metal disc on pillar (DOP) substrates with as few as a single disc to large densities of DOPs with both regular periodic shapes and configured as random structures that mimic synthetically prepared colloidal aggregates. Enhancements reaching 10exp9 are achieved on optimized DOPs, wherein optimization depends on factors that include underlying layers, the size, shapes, and proximity of individual and groupings of DOPs, and pillar heights.

Code: FOB	Time Slot/Poster Number: 09:20 - 09:40 am	Session: SERS (Substrates, Single Molecule, Theory) II
Single Molecule SERS with Nanogap-engineered gold-silver core-shell nanodumbbells (GSND)
Yung Doug Suh
Laboratory for Advanced Molecular Probing (LAMP),, Daejeon, South Korea
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Summary
A single molecule SERS detection strategy with gold–silver core–shell nanodumbbells(GSND), where the gap between two nanoparticles and the Raman-dye position and environment can be engineered on the nanoscale using DNA hybridization, will be presented. Atomic-force-microscope-correlated nano-Raman measurements of individual dumbbell structures demonstrate that Raman signals can be repeatedly detected from single-DNA-tethered nanodumbbells [1]. Reference [1] D.-K.Lim, K.-S.Jeon, H.M. Kim, J.-M.Nam, and Y.D.Suh, Nature Materials 9 (Jan 2010) 60.

Code: FOB	Time Slot/Poster Number: 09:40 - 10:00 am	Session: SERS (Substrates, Single Molecule, Theory) II
The Silver Nanorod Array SERS Substrates
Yiping Zhao; Yongjun Liu
The University of Georgia, Athens, GA
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Summary
Silver nanorod array substrates fabricated by oblique angle deposition method have shown very high SERS enhancement factor. The SERS enhancement factor depends strongly on the nanorod length, the fabrication conditions, and the configurations of the excitation laser beam. A simple modified Greenler’s model is proposed to qualitatively explain those effects. The possible origin for the high enhancement has been studied, and we have found that the side surfaces of the nanorod arrays contributes more to the SERS enhancement compared to the ends. We propose that this is due to the anisotropic absorbance nature of the Ag nanorod substrates.