The molecular level specificity provided by Raman spectroscopy (RS) has made it a widely used spectroscopic tool for the determination of molecular structure and compound identification. Dr. Tyagi’s group has been studying Surface Enhanced Raman Scattering (SERS) in fractal aggregates fabricated from nano-particle printing inks. Fractal aggregates of metallic colloidal particles can provide hyper- enhancement for various linear and nonlinear optical responses, including RS. Such enhancement results from the localization of optical plasmon excitations within small parts (“hot-spots” a few to tens of nm in size) of a fractal aggregate. Since fractals are scale-invariant they, unlike translationally-invariant media, do not support propagating waves and hence can ‘trap’ electromagnetic field in very small volumes. When sufficiently concentrated, the large electromagnetic fields in the hot spots can result in very large SERS enhancement.
Nanotechnology Commercialization in Pennsylvania
“Across the world, the competition to find the next great scientific advancement continues to grow… as a competitor in the global marketplace, it is Pennsylvania’s responsibility to give our universities, companies and partners the best opportunties to be on the forefront of these advancements.”
–The Honorable Edward G. Rendell
Governor of Pennsylvania