Spectroscopy with planar optical waveguides is an active field of research for the quantitative analysis of various supramolecular surface architectures and processes, and for applications in integrated optical chip communication, direct chemical sensing, etc. In this contribution in collaboration with other leading research groups in the field, we summarize some recent development in optical waveguide spectroscopy using nanoporous thin films as the planar substrates that can guide the light just as well as bulk thin films.
This is because the nanoporosity is at a spatial length-scale that is far below the wavelength of the guided light; hence, it does not lead to an enhanced scattering or additional losses of the optical guided modes. The pores have mainly two effects: they generate an enormous inner surface (up to a factor of 100 higher than the mere geometric dimensions of the planar substrate), and they allow for the exchange of material and charges between the two sides of the solid thin film.
Researchers of BIMat has in particular contributed ways to manufacture nanoporous waveguides and studying the potential application of such waveguides to biological membrane research.
The article is published in Analytical and Bioanalytical Chemistry as Nanoporous thin films in optical waveguide spectroscopy for chemical analytics.