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.

 

Spectral phase shaping for high resolution CARS

(full pdf)

A. C. W. van Rhijn, S. Postma, J. P. Korterik, J. L. Herek, and H. L. Offerhaus
SPIE proceedings
vol 7183 p.71830X february 13, 2009
doi:10.1117/12.808792

By spectral phase shaping of both the pump and probe pulses in coherent anti-Stokes Raman scattering (CARS) spectroscopy we demonstrate the extraction of the frequencies of vibrational lines using an unamplified oscillator. Furthermore we demonstrate chemically selective broadband CARS microscopy on a mixed sample of 4 μm diameter polystyrene (PS) and poly(methyl methacrylate) (PMMA) beads. The CARS signal from either the PS or the PMMA beads is shown to be enhanced or suppressed, depending on the phase profile applied to the broadband spectrum. Using a combination of negative and positive (sloped) π-phase steps in the pump and probe spectrum the purely non-resonant background signal is removed.
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