SERS Amplification from Self-Organized Arrays of Plasmonic Nanocrescents.

We report on the surface-enhanced Raman scattering (SERS) efficiency of self-organized arrays of Au nanocrescents confined on monolayers of polystyrene nanospheres. A dichroic SERS emission in the visible spectrum is observed due to the selective excitation of a localized surface plasmon (LSP) resonance along the "short axis" of the Au nanocrescents. Under these conditions SERS signal amplifications in the range of 10(3) have been observed with respect to a flat reference Au film. The far field and near field plasmonic response of Au nanocrescent arrays have been investigated as a function of the metal dose deposited onto the polymeric spheres. In this way, we show the possibility of simply tailoring the SERS emission by engineering the morphology of the plasmonic nanocrescents. We highlight the SERS activity of chains of satellite nanoclusters that decorate the border of each connected crescent and sustain isotropic high energy LSP resonances in the visible spectrum.

[1]  L. Andreani,et al.  A Multi‐optical Collector of Sunlight Employing Luminescent Materials and Photonic Nanostructures , 2016 .

[2]  D. Massabò,et al.  Self-organized metal nanowire arrays with tunable optical anisotropy , 2008 .

[3]  S. Retterer,et al.  Free-standing optical gold bowtie nanoantenna with variable gap size for enhanced Raman spectroscopy. , 2010, Nano letters.

[4]  Andrea Toma,et al.  Gold Dimer Nanoantenna with Slanted Gap for Tunable LSPR and Improved SERS , 2014 .

[5]  Ben M. Maoz,et al.  Solid-State Thermal Dewetting of Just-Percolated Gold Films Evaporated on Glass: Development of the Morphology and Optical Properties , 2013 .

[6]  Cristiano D'Andrea,et al.  Optical nanoantennas for multiband surface-enhanced infrared and Raman spectroscopy. , 2013, ACS nano.

[7]  Javier Aizpurua,et al.  Metallic nanoparticle arrays: a common substrate for both surface-enhanced Raman scattering and surface-enhanced infrared absorption. , 2008, ACS nano.

[8]  Federico Capasso,et al.  Self-Assembled Plasmonic Nanoparticle Clusters , 2010, Science.

[9]  M. Meneghetti,et al.  Exploring How to Increase the Brightness of Surface‐Enhanced Raman Spectroscopy Nanolabels: The Effect of the Raman‐Active Molecules and of the Label Size , 2012 .

[10]  J. Heberle,et al.  Biochemical applications of surface-enhanced infrared absorption spectroscopy , 2007, Analytical and bioanalytical chemistry.

[11]  Annemarie Pucci,et al.  Resonant plasmonic and vibrational coupling in a tailored nanoantenna for infrared detection. , 2008, Physical review letters.

[12]  O. Maragò,et al.  Red shifted spectral dependence of the SERS enhancement in a random array of gold nanoparticles covered with a silica shell: extinction versus scattering , 2015 .

[13]  Sivashankar Krishnamoorthy,et al.  Nanoparticle cluster arrays for high-performance SERS through directed self-assembly on flat substrates and on optical fibers. , 2012, ACS nano.

[14]  Yiping Zhao,et al.  Novel nanostructures for SERS biosensing , 2008 .

[15]  Valentina Robbiano,et al.  Second Harmonic Generation Circular Dichroism from Self‐Ordered Hybrid Plasmonic–Photonic Nanosurfaces , 2014 .

[16]  N. Pavillon,et al.  Laser-targeted photofabrication of gold nanoparticles inside cells , 2014, Nature Communications.

[17]  Ivano Alessandri,et al.  Recyclable SERS substrates based on Au-coated ZnO nanorods. , 2011, ACS applied materials & interfaces.

[18]  Luke P. Lee,et al.  Nanophotonic crescent moon structures with sharp edge for ultrasensitive biomolecular detection by local electromagnetic field enhancement effect. , 2005, Nano letters.

[19]  A. Hohenau,et al.  Revisiting Surface-Enhanced Raman Scattering on Realistic Lithographic Gold Nanostripes , 2013, The journal of physical chemistry. C, Nanomaterials and interfaces.

[20]  O. Muskens,et al.  Optical response of a single noble metal nanoparticle , 2006 .

[21]  J. M. Baik,et al.  Polarization-dependent surface-enhanced Raman scattering from a silver-nanoparticle-decorated single silver nanowire. , 2008, Nano letters.

[22]  Harald Giessen,et al.  Hole-mask colloidal nanolithography for large-area low-cost metamaterials and antenna-assisted surface-enhanced infrared absorption substrates. , 2012, ACS nano.

[23]  A. Toma,et al.  Self-organized ion-beam synthesis of nanowires with broadband plasmonic functionality , 2010 .

[24]  P. Etchegoin,et al.  Raman spectroscopy and related optical techniques , 2009 .

[25]  Urs Sennhauser,et al.  Atomically flat single-crystalline gold nanostructures for plasmonic nanocircuitry. , 2010, Nature communications.

[26]  Yiping Zhao,et al.  The Use of Aligned Silver Nanorod Arrays Prepared by Oblique Angle Deposition as Surface Enhanced Raman Scattering Substrates , 2008 .

[27]  Steven R. Emory,et al.  Probing Single Molecules and Single Nanoparticles by Surface-Enhanced Raman Scattering , 1997, Science.

[28]  Federico Capasso,et al.  Optical properties of surface plasmon resonances of coupled metallic nanorods. , 2007, Optics express.

[29]  Nikolai G Khlebtsov,et al.  Gold nanoisland films as reproducible SERS substrates for highly sensitive detection of fungicides. , 2015, ACS applied materials & interfaces.

[30]  J. Venables,et al.  Nucleation and growth of thin films , 1984 .

[31]  C. Haynes,et al.  Nanosphere lithography: Tunable localized surface plasmon resonance spectra of silver nanoparticles , 2000 .

[32]  F. Tantussi,et al.  SERS Enhancement and Field Confinement in Nanosensors Based on Self-Organized Gold Nanowires Produced by Ion-Beam Sputtering , 2014 .

[33]  Eric C. Le Ru,et al.  Principles of Surface-Enhanced Raman Spectroscopy: And Related Plasmonic Effects , 2008 .

[34]  A. Rosato,et al.  Magneto-plasmonic Au-Fe alloy nanoparticles designed for multimodal SERS-MRI-CT imaging. , 2014, Small.

[35]  Richard W. Taylor,et al.  In Situ SERS Monitoring of Photochemistry within a Nanojunction Reactor , 2013, Nano letters.

[36]  P. Pastore,et al.  Efficient AuFeOx Nanoclusters of Laser-Ablated Nanoparticles in Water for Cells Guiding and Surface-Enhanced Resonance Raman Scattering Imaging , 2014 .

[37]  J. Baumberg,et al.  Enhancing solar cells with localized plasmons in nanovoids , 2011, CLEO: 2011 - Laser Science to Photonic Applications.

[38]  Peter Nordlander,et al.  Electromigrated nanoscale gaps for surface-enhanced Raman spectroscopy. , 2007, Nano letters.

[39]  H. Möhwald,et al.  Nanoplasmonic chitosan nanofibers as effective SERS substrate for detection of small molecules. , 2015, ACS applied materials & interfaces.

[40]  M. Moskovits.  Surface‐enhanced Raman spectroscopy: a brief retrospective , 2005 .

[41]  Yuji Nishikawa,et al.  Surface-Enhanced Infrared Spectroscopy: The Origin of the Absorption Enhancement and Band Selection Rule in the Infrared Spectra of Molecules Adsorbed on Fine Metal Particles , 1993 .

[42]  S. Kawata,et al.  Plasmonics for near-field nano-imaging and superlensing , 2009 .

[43]  J. Baumberg,et al.  SERS from molecules bridging the gap of particle-in-cavity structures. , 2011, Chemical communications.

[44]  Duncan Graham,et al.  Comparison of resonant and non resonant conditions on the concentration dependence of surface enhanced Raman scattering from a dye adsorbed on silver colloid , 2002 .

[45]  Michel Bosman,et al.  Encapsulated Annealing: Enhancing the Plasmon Quality Factor in Lithographically–Defined Nanostructures , 2014, Scientific Reports.

[46]  M. Allegrini,et al.  Re-radiation enhancement in polarized surface-enhanced resonant Raman scattering of randomly oriented molecules on self-organized gold nanowires. , 2011, ACS nano.

[47]  Sang‐Hyun Oh,et al.  Single‐Crystalline Silver Films for Plasmonics , 2012, Advanced materials.

[48]  S. Kawata,et al.  Dynamic SERS imaging of cellular transport pathways with endocytosed gold nanoparticles. , 2011, Nano letters.

[49]  Jennifer S. Shumaker-Parry,et al.  Fabrication of Crescent‐Shaped Optical Antennas , 2005 .

[50]  F. D. Stasio,et al.  Hybrid Plasmonic–Photonic Nanostructures: Gold Nanocrescents Over Opals , 2013 .

[51]  Michele Dipalo,et al.  Out-of-Plane Plasmonic Antennas for Raman Analysis in Living Cells. , 2015, Small.

[52]  S. Dai,et al.  Robust SERS Substrates Generated by Coupling a Bottom-Up Approach and Atomic Layer Deposition , 2010 .

[53]  Kuo-Ping Chen,et al.  Drude relaxation rate in grained gold nanoantennas. , 2010, Nano letters.