## [#  Surface-enhanced optical phenomena 

 ](/research-areas/surface-enhanced-optical-phenomena)

Ever since an experimental observation (1974) of large Raman scattering cross sections from pyridine molecules adsorbed onto silver electrodes, there have been considerable efforts to understand and produce materials demonstrating “surface-enhancement.” Metallic, nanostructured substrates have the ability to generate intense optical fields localized to subwavelength regions that are orders of magnitude larger than the incident optical fields. These enhanced fields can amplify certain optical effects, such as Raman scattering, fluorescence, harmonic generation, and four-wave mixing. We are working on developing different types of surfaces that enhance these processes, for applications in molecular sensing and spectroscopy.