Optical Sciences

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 MESA+ institute.
We participate in the EU-COST actions MP1102: Coherent Raman microscopy (MicroCor) and CM1202: Supramolecular photocatalytic water splitting (PERSPECT-H2O)

 

TAPPING MODE ATOMIC-FORCE MICROSCOPY IN LIQUID

(full pdf)

PUTMAN CAJ, VANDERWERF KO, DEGROOTH BG, VANHULST NF, GREVE J
APPLIED PHYSICS LETTERS
vol 64 issue 18: p2454-p2456 MAY 2 1994

We show that standard silicon nitride cantilevers can be used for tapping mode atomic force microscopy (AFM) in air, provided that the energy of the oscillating cantilever is sufficiently high to overcome the adhesion of the water layer. The same cantilevers are successfully used for tapping mode AFM in liquid. Acoustic modes in the liquid excite the cantilever. o­n soft samples, e.g., biological material, this tapping mode AFM is much more gentle than the regular contact mode AFM. Not o­nly is the destructive influence of the lateral forces minimized, but more important, the intrinsic viscoelastic properties of the sample itself are effectively used to ''harden'' the soft sample.
Printable version