Presentations

    Isolating surface-enhanced Raman scattering hot spots using surface-enhanced multiphoton lithography, at Photonics West 2010 (San Francisco, CA), Monday, January 25, 2010:
    We present a method for improving femtomole-level trace detection (10^9 molecules) using large-area surface-enhanced Raman scattering (SERS) substrates. Using multiphoton-induced exposure of a commercial photoresist, we physically limit the available molecular adsorption sites to only the electromagnetic “hot spots” on the substrate. This process prevents molecules from adsorbing to sites of weak SERS enhancement, while permitting adsorption to sites of extraordinary SERS enhancement. For a randomly adsorbed submonolayer of benzenethiol molecules the average Raman scattering cross section of... Read more about Isolating surface-enhanced Raman scattering hot spots using surface-enhanced multiphoton lithography
    Nonlinear plasmonics: SERS hot spot isolation and enhanced laser cell transfection, at Stanford University (Stanford, CA), Tuesday, January 26, 2010:
    Surface-enhanced Raman scattering (SERS) is one of the most sensitive molecular spectroscopy techniques currently available. Using SERS, it is possible to obtain vibrational spectra from chemical quantities as small as a single molecule. However, it is challenging to have molecules of interest adsorb specifically to a substrate’s “hot spots,” or regions of largest electromagnetic enhancement. I will describe a nonlinear optical technique that masks SERS substrates such that only hot spots are available as molecular adsorption sites. Using this approach, we have demonstrated a 27-fold... Read more about Nonlinear plasmonics: SERS hot spot isolation and enhanced laser cell transfection
    Nonlinear plasmonics: SERS hot spot isolation and enhanced laser cell transfection, at UCLA IEEE photonics society seminar, University of California, Los Angeles (Westwood, CA), Thursday, February 4, 2010:
    Surface-enhanced Raman scattering (SERS) is one of the most sensitive molecular spectroscopy techniques currently available. Using SERS, it is possible to obtain vibrational spectra from chemical quantities as small as a single molecule. However, it is challenging to have molecules of interest adsorb specifically to a substrate’s “hot spots,” or regions of largest electromagnetic enhancement. I will describe a nonlinear optical technique that masks SERS substrates such that only hot spots are available as molecular adsorption sites. Using this approach, we have demonstrated a 27-fold... Read more about Nonlinear plasmonics: SERS hot spot isolation and enhanced laser cell transfection
    Nonlinear plasmonics: SERS hot spot isolation and enhanced laser cell transfection, at Northwestern University (Evanston, IL), Thursday, February 25, 2010
    Surface-enhanced Raman scattering (SERS) is one of the most sensitive molecular spectroscopy techniques currently available. Using SERS, it is possible to obtain vibrational spectra from chemical quantities as small as a single molecule. However, it is challenging to have molecules of interest adsorb specifically to a substrate’s “hot spots,” or regions of largest electromagnetic enhancement. I will describe a nonlinear optical technique that masks SERS substrates such that only hot spots are available as molecular adsorption sites. Using this approach, we have demonstrated a 27-fold... Read more about Nonlinear plasmonics: SERS hot spot isolation and enhanced laser cell transfection
    Plasmon-enhanced ultrafast laser cell transfection, at Photonics West 2011 (San Francisco, CA), Sunday, January 23, 2011:
    We present a method for transfecting biological cells using ultrafast plasmons excited on large areas of bio-compatible, nano-pyramid substrates. This technique does not employ any potentially toxic chemical transfection reagents or metallic nanoparticles. Leveraging the field enhancement supported by these pyramidal plasmonic nanostructures, we generate localized, transient pores in the membranes of large numbers of cells at a rate of approximately 10^4 per second. Diffusion through these pores enables the delivery of functional short interfering RNA (siRNA) molecules into the cells. We... Read more about Plasmon-enhanced ultrafast laser cell transfection