Integrated Optical Sciences
Biomolecules and nanostructures
The Optical Sciences group studies the interaction of light and matter. Our current focus is on detection and sensing/imaging with an emphasis on the development of integrated photonics. We are part of Twente University's Department of Science and Technology and member of the MESA+ institute.
Plasmon-Enhanced Organic Photovoltaics
Organic photovoltaics (OPVs) are cheap alternatives to silicon-based solar cells, reaching power conversion efficiencies ˜9 % for single junction solar cells. Commercialization of OPVs can spark into life once the efficiency well exceeds 10 %!  An important factor currently limiting the efficiency is the lack of light absorption in the (infra-)red wavelength range. Increasing the active layer thickness improves light absorption, however complicates charge transport. Development of novel materials may allow to utilize photons the (infra-)red, but leads to a detrimental drop in open circuit voltage. Introduction of plasmonic antennas, optionally functionalized with upconversion materials, allows to harvest the (infra-)red part of the solar spectrum while maintaining a high open circuit voltage and efficient charge transport, and shows the prospect of realizing a commercializable OPV.
We are using Lumerical's FDTD simulation software to establish the geometrical parameters of the plasmonic antennas and OPV device leading to maximum enhancement in light absorption. Our results show that the actual enhancement is very sensitize to these parameters, and that optimization has the potential to enhance the OPV efficiency to values exceeding 10 %.
1. M. C. Scharber and N. S. Sariciftci, Prog Polym Sci 38 (12), 1929-1940 (2013).
2. C. J. Brabec, S. Gowrisanker, J. J. M. Halls, D. Laird, S. J. Jia and S. P. Williams, Adv Mater 22 (34), 3839-3856 (2010).