Biomolecules and nanostructures
The Optical Sciences group studies the interaction of light and matter at the nanoscale.
We do this by exploring ways to shape light and its environment. It's what we call
active and passive control. Our current focus is on the interaction of light with
biomolecules and nanostructures. We are part of Twente
University's Department of Science and Technology and member of the
On the role of electromagnetic boundary conditions in single molecule fluorescence lifetime studies of dyes embedded in thin films(full pdf)
Vallee R, Tomczak N, Gersen H, van Dijk EMHP, Garcia-Parajo MF, Vancso GJ, van Hulst NF
CHEMICAL PHYSICS LETTERS
vol 348 issue 3-4: p161-p167 NOV 9 2001
Single molecule fluorescence lifetime studies are generally performed in thin polymer films, where the influence of the interface on the behaviour of fluorescing molecules is not negligible. In order to describe this influence, we investigate annealed films of different thickness. We show that the distribution of fluorescence lifetimes of the embedded dyes is shifted to lower values as the thickness of the film increases. We explain this shift by simple electromagnetic arguments related to the boundary conditions at the interfaces of the polymer film with air and glass, respectively. The conclusion is that extreme care must be taken in order to interpret single molecule data with respect to the true chemical nature of the phenomena. (C) 2001 Elsevier Science B.V. All rights reserved.