Orthogonal trapping and sensing with long working distance optics [invited]

We are developing a next generation BioPhotonics Workstation to be applied in research on regulated microbial cell growth including their underlying physiological mechanisms, in vivo characterization of cell constituents and manufacturing of nanostructures and meta-materials. The workstation will enable us to strongly expand the field of laser manipulation and diagnostics of the motion and structure of macromolecular systems. In particular, combining our new spatial light modulating techniques with the unique properties of ultrashort laser pulses we aim at constructing a multi-purpose BioPhotonics Workstation that allows the user to directly control and simultaneously measure a portfolio of important chemical and biological processes. We arc currently able to generate up to 100 powerful optical traps using well-separated objectives, which eliminates the need for high numerical aperture oil or water immersion objectives required in conventional optical tweezers. This generates a large field of view and leaves vital space for integrating other enabling tools for probing the trapped particles, such as linear and nonlinear microscopy or micro-spectroscopy. Together with chcmists at another Danish university this has been illustrated by CARS and fluorescence spectroscopy of trapped polystyrene beads where the side view geometry opens intriguing possibilities for accessing trapped particles with optical as well as other types of probe methods independent from the trapping process2.