Co-founder (CTO) at Holloid

I develop Digital Holographic Microscopy at the BOKU to study self-assembly in colloidal systems, measure forces between colloidal particles, study the interactions between bacteria and substrates and identify cells and bacteria.

PhD student of physics at the University of Utrecht. I am responsiblefor the maintenance and further development of theoptical tweezers setup and the confocals in our lab. Togetherwith people at the New York University I developed a holographictechnique to track and characterize individual particlesin three dimensions at unprecedented accuracy using in-lineholography and Mie-scattering. By numerically solving the inverseproblem posed by the interference pattern below a coherentlyilluminated Mie-particle, we can determine the position inthree dimensions with nm accuracy while also measuring theindividual particle’s radius and refractive index. Using a fastCCD camera we can track particles with an resolution in timeand space. Using optical tweezers I can place multiple particlesin interesting configurations to measure the interaction forces.These interaction forces can be the result the charge on the particlesand screening, but can also be caused by electric dipolesthat we induce by applying high frequency electric fields or bythe presence of other, refractive index matched particles thatinduce a depletion attraction. I gained experience with a widevariety of particles, solvents and techniques. Moreover, I haveperformed calculations on the trapping forces of optical tweezersin a wide parameter space to explore the possibilities.

Applied Physics (University Twente, Enschede) Group: PoF (Physics of Fluids)Graduation assignment: a study of the Path-, Wake- and Shape-Oscillations of a Rising bubble. In many applications rising bubbles play a crucial role. Rising bubbles greatly increase the exchange of gasses. For instance, CO2 is being removed from the atmosphere by algae after being dissolved from a bubble. My work on the topic entails the further development of an experimental setup used to stereoscopically film rising bubbles. I wrote a program in Matlab to analyze the results of these experiments. I have been able to calculate the three dimensional shape of the bubbles from the information gathered from the two mutually perpendicular views. Moreover the setup also uses Schlieren optics to visualize the wake of the bubble.