Introduction of Nanoplasmonics 2011 Spring Semester

What we are going to deal with Metallic Nanoparticle or 2-D Nanostructure Metallic Thin Film and Light!!!

Examples of Metallic Nanoparticles (Standalone)

Examples of Metallic Nanostructures (2D)

What if the size of metallic particle is down to nanoscale? Surface Plasmon Resonance, Photothermal Effect and Strong field enhancement

Surface Plasmon Resonance White light Excitation Group oscillation of electron cloud Noble metal nano-structure Extinction Resonance Frequency f Displacement Resonance Frequency k c m F(t) = x

W. A. Murray, W. L. Barnes, Adv. Mat. (2007) Multi wavelength excitation Extinction Selective Re-radiation (i.e. Scattering) Material, Size, and Shape Dependent Optical Antenna!!! Selective Target releasing by noble nanoparticles

LvqQ&feature=relatedhttp:// LvqQ&feature=related Surface Plasmon Resonance in Metallic Thin Film

Applications of plasmonic photothermal conversion Laser-induced size-reduction of metallic nanoparticles Control of gene regulation or protein expression in cell Targeted local thermotherapy of cancer Local drug delivery by optical switch Optically driven collective oscillation of electrons Plain Nanosphere Nanocrescent Collision of electrons with lattice: Phonon relaxation Excitation of molecular vibrations in ambience E ,  T   T < 10 K or Require local high power/pulsed lasers Direct conversion of optical energy into heat Photothermal Conversion

Strong Field Enhancement Conventional Lens Focusing Focused Spot d ~ * * : Wavelength Plasmonic Lens Focusing Target molecules Lens >> /nm Intensity (A.U.) Molecular Fingerprint Highly focused EM field High Sensitivity Spatial Resolution

Stained Glass & Roman Cup

Applications of Nanoplasmonics From Catalysis to Biology

Applications of plasmonic photothermal conversion Laser-induced size-reduction of metallic nanoparticles Control of gene regulation or protein expression in cell Targeted local thermotherapy of cancer Local drug delivery by optical switch Optically driven collective oscillation of electrons Plain Nanosphere Nanocrescent Collision of electrons with lattice: Phonon relaxation Excitation of molecular vibrations in ambience E ,  T   T < 10 K or Require local high power/pulsed lasers Direct conversion of optical energy into heat Photothermal Conversion

3J9aUQSK_QE Video Clip for Photothermal Effect

Photothermal Therapy

ONCOS * Molecular Therapeutics: Example ONCOS

Strong Field Enhancement Conventional Lens Focusing Focused Spot d ~ * * : Wavelength Plasmonic Lens Focusing Target molecules Lens >> /nm Intensity (A.U.) Molecular Fingerprint Highly focused EM field High Sensitivity Spatial Resolution

Excitation Raman Scattering Good: Molecular fingerprint signatures Label-free detection Bad: Signal too weak Molecule Raman Scattering *SERS: Surface-enhanced Raman Scattering SERS Metallic Nanostructure Adsorbed Molecule Excitation Raman Scattering Field Enhancement Improving Raman scattering by double field enhancement Raman Signal Enhancement  Local Field Enhancement  4 Raman molecular fingerprint spectrum Single Molecule Detection by SERS*

Last Video Clip for This Hour de_play/?doi= /ETHZ/AV- 9b0a8bfb-a42e-49c bbd643ddc7a8