Superchiral surface waves for surface enhanced chiroptical spectroscopy.

Pellegrini G., Mogni E., Jil-Rostra J., Yubero F., Simone G., Fossati S., Dostálek J., Martinez Vázquez R., Osellame R., Celebrano M., Finazzi M., Biagioni P.
  Lunedì 12/09   14:00 - 19:00   Aula D - Marianna Ciccone   II - Fisica della materia   Presentazione
Chirality is ubiquitous in nature and accordingly in the modern pharmaceutical industry, where the vast majority of newly developed drugs is chiral. Chiroptical techniques employ polarized light for the molecular structure characterization and are flexible, low-cost, and time-efficient. Yet, their limited sensitivity prevents their integration for on-chip chiral analysis. We introduce the concept of superchiral surface waves at the surface of dielectric multilayers, and design a platform capable of a two orders of magnitude signal enhancement in the analysis of chiral molecules compared to standard illumination, with broadband spectral operation and arbitrarily large active area, based on the superposition of TE and TM Bloch surface waves. We experimentally fabricate and characterize such a platform. We finally demonstrate how genetically evolved multilayers can support superchiral surface waves from the ultraviolet to the near infrared regime. These findings pave the way towards the integration of chiroptical techniques with microfluidic networks, enriching the widespread lab-on-chip technology with new functionalities not available so far.