Optical near-field mapping of plasmonic nanoprisms.

The optical local-field enhancement on nanometer length scales provides the basis for plasmonic metal nanostructures to serve as molecular sensors and as nanophotonic devices. However, particle morphology and the associated surface plasmon resonance alone do not uniquely reflect the important details of the local field distribution. Here, we use interferometric homodyne tip-scattering near-field microscopy for plasmonic near-field imaging of crystalline triangular silver nanoprisms. Strong spatial field variation on lengths scales as short as 20 nm are observed sensitively depending on structural details and environment. The poles of the dipole and quadrupole plasmon modes, as identified by phase-sensitive probing and calculations performed in the discrete dipole approximation (DDA), reflect the particle symmetry. Together with the observation that the largest enhancement is not necessarily found to be associated with the tips of the nanoprisms, our results provide critical information for the selection of particle geometries as building blocks for plasmonic device applications.

[1]  Quang Nguyen,et al.  Simple model for the polarization effects in tip-enhanced Raman spectroscopy , 2007 .

[2]  Bernhard Lamprecht,et al.  Design of multipolar plasmon excitations in silver nanoparticles , 2000 .

[3]  Rainer Hillenbrand,et al.  Pseudoheterodyne detection for background-free near-field spectroscopy , 2006 .

[4]  A. Halm,et al.  Nanomechanical Control of an Optical Antenna , 2008, 2007 European Conference on Lasers and Electro-Optics and the International Quantum Electronics Conference.

[5]  F. Keilmann,et al.  Phonon-enhanced light–matter interaction at the nanometre scale , 2002, Nature.

[6]  F. J. García de abajo,et al.  Probing the photonic local density of states with electron energy loss spectroscopy. , 2007, Physical review letters.

[7]  J. Aizpurua,et al.  Infrared imaging of single nanoparticles via strong field enhancement in a scanning nanogap. , 2006, Physical review letters.

[8]  F. Keilmann,et al.  Near-field microscopy by elastic light scattering from a tip , 2004, Philosophical Transactions of the Royal Society of London. Series A: Mathematical, Physical and Engineering Sciences.

[9]  C. Mirkin,et al.  Controlling anisotropic nanoparticle growth through plasmon excitation , 2003, Nature.

[10]  J. Kottmann,et al.  Spectral response of plasmon resonant nanoparticles with a non-regular shape. , 2000, Optics express.

[11]  D. Kim,et al.  Vector field mapping of local polarization using gold nanoparticle functionalized tips: independence of the tip shape. , 2007, Optics express.

[12]  Byoungho Lee,et al.  On the concept of imaging nanoscale vector fields , 2007 .

[13]  D. A. Stuart,et al.  In vivo glucose measurement by surface-enhanced Raman spectroscopy. , 2006, Analytical chemistry.

[14]  Markus B. Raschke,et al.  Scanning-probe Raman spectroscopy with single-molecule sensitivity , 2006 .

[15]  Thomas R Huser,et al.  Surface-enhanced Raman scattering from individual au nanoparticles and nanoparticle dimer substrates. , 2005, Nano letters.

[16]  A. Hohenau,et al.  Silver nanowires as surface plasmon resonators. , 2005, Physical review letters.

[17]  D. P. O'Neal,et al.  Photo-thermal tumor ablation in mice using near infrared-absorbing nanoparticles. , 2004, Cancer letters.

[18]  George C Schatz,et al.  Observation of a quadrupole plasmon mode for a colloidal solution of gold nanoprisms. , 2005, Journal of the American Chemical Society.

[19]  L. A. Bumm,et al.  Near-field spectroscopy of surface plasmons in flat gold nanoparticles. , 2007, Optics letters.

[20]  E. Coronado,et al.  The Optical Properties of Metal Nanoparticles: The Influence of Size, Shape, and Dielectric Environment , 2003 .

[21]  Younan Xia,et al.  Shape-Controlled Synthesis of Gold and Silver Nanoparticles , 2002, Science.

[22]  Hui Zhang,et al.  Gold nanocages: bioconjugation and their potential use as optical imaging contrast agents. , 2005, Nano letters.

[23]  I. Smolyaninov,et al.  Surface plasmon dielectric waveguides , 2005, 2006 Conference on Lasers and Electro-Optics and 2006 Quantum Electronics and Laser Science Conference.

[24]  J. Aizpurua,et al.  Coherent imaging of nanoscale plasmon patterns with a carbon nanotube optical probe , 2003 .

[25]  Federico Capasso,et al.  Plasmonic laser antenna , 2006 .

[26]  David L. Carroll,et al.  Synthesis and Characterization of Truncated Triangular Silver Nanoplates , 2002 .

[27]  Younan Xia,et al.  Reduction by the End Groups of Poly(vinyl pyrrolidone): A New and Versatile Route to the Kinetically Controlled Synthesis of Ag Triangular Nanoplates , 2006 .

[28]  Z. Wang,et al.  Transmission Electron Microscopy of Shape-Controlled Nanocrystals and Their Assemblies , 2000 .

[29]  Adam D. McFarland,et al.  Single Silver Nanoparticles as Real-Time Optical Sensors with Zeptomole Sensitivity , 2003 .

[30]  Michael Vollmer,et al.  Optical properties of metal clusters , 1995 .

[31]  C. Mirkin,et al.  Localized surface plasmon resonance spectroscopy of single silver triangular nanoprisms. , 2006, Nano letters.

[32]  B. Djafari-Rouhani,et al.  Photon, electron, magnon, phonon and plasmon mono-mode circuits , 2004 .

[33]  J. West,et al.  Near-infrared resonant nanoshells for combined optical imaging and photothermal cancer therapy. , 2007, Nano letters.

[34]  A. Haes,et al.  A unified view of propagating and localized surface plasmon resonance biosensors , 2004, Analytical and bioanalytical chemistry.

[35]  Dong Ha Kim,et al.  Apertureless near-field vibrational imaging of block-copolymer nanostructures with ultrahigh spatial resolution. , 2005, Chemphyschem : a European journal of chemical physics and physical chemistry.

[36]  Nastassja A. Lewinski,et al.  Optically tunable nanoparticle contrast agents for early cancer detection: model-based analysis of gold nanoshells. , 2005, Journal of biomedical optics.

[37]  Harry A. Atwater,et al.  Local detection of electromagnetic energy transport below the diffraction limit in metal nanoparticle plasmon waveguides , 2003, Nature materials.

[38]  L. Novotný,et al.  On the concept of imaging nanoscale vector fields , 2007 .

[39]  G S Kino,et al.  Improving the mismatch between light and nanoscale objects with gold bowtie nanoantennas. , 2005, Physical review letters.

[40]  L. Liz‐Marzán,et al.  Mapping surface plasmons on a single metallic nanoparticle , 2007 .

[41]  Keiko Munechika,et al.  Dependence of fluorescence intensity on the spectral overlap between fluorophores and plasmon resonant single silver nanoparticles. , 2007, Nano letters.

[42]  Younan Xia,et al.  Gold nanocages as contrast agents for spectroscopic optical coherence tomography. , 2005, Optics letters.

[43]  B. Draine,et al.  Discrete-Dipole Approximation For Scattering Calculations , 1994 .

[44]  Peter Nordlander,et al.  Plasmonic nanostructures: artificial molecules. , 2007, Accounts of chemical research.

[45]  M. Ratner,et al.  Multipolar excitation in triangular nanoprisms. , 2005, The Journal of chemical physics.

[46]  Glenn P. Goodrich,et al.  Plasmonic enhancement of molecular fluorescence. , 2007, Nano letters.

[47]  E. Ozbay.  Plasmonics: Merging Photonics and Electronics at Nanoscale Dimensions , 2006, Science.

[48]  John A. Rogers,et al.  Apertureless scanning near-field optical microscopy: a comparison between homodyne and heterodyne approaches , 2006 .

[49]  C. Mirkin,et al.  Nanoparticles with Raman spectroscopic fingerprints for DNA and RNA detection. , 2002, Science.

[50]  Catherine J Murphy,et al.  Seeded high yield synthesis of short Au nanorods in aqueous solution. , 2004, Langmuir : the ACS journal of surfaces and colloids.