Chemically selective imaging with single pulse CARS microscopy

PHYS 510

Allison G. Caster,, Department of Chemistry, University of California at Berkeley, 1 Cyclotron Rd. Mail Stop 2-300, Berkeley, CA 94720, Sang-Hyun Lim,, Department of Chemistry and Biochemistry, University of Texas at Austin, 1 University Station A5300, Austin, TX 78712, Olivier Nicolet, Lawrence Berkeley National Lab, 1 Cyclotron Rd., Mail Stop 2R0300, Berkeley, CA 94720, and Stephen R. Leone,, Departments of Chemistry and Physics, University of California at Berkeley / Lawrence Berkeley National Lab, 209 Gilman Hall, Department of Chemistry, Berkeley, CA 94720.
With coherent anti-Stokes Raman scattering (CARS) spectroscopy it is possible to identify the chemical composition of a sample without the need for extrinsic labels and with orders of magnitude greater sensitivity than can be achieved with spontaneous Raman scattering. With a new CARS technique, phase and polarization pulse shaping of a single ultrafast broadband pulse is used to control the spectral interference between the resonant and non-resonant signals from the same sample. Within a few milliseconds, the difference between two simultaneously acquired interference signals provides an amplified, background-free CARS spectrum with more than 1000 cm-1 of bandwidth. The full fingerprint-region vibrational spectrum is used as a contrast mechanism for imaging various polymer and lipid samples with a spatial resolution of 400 nm. This fast, high-resolution, chemically selective imaging is desirable for understanding systems from polymer photoresists to biological cells, especially for the characterization of lipid ordering in cell membranes.

Poster Session
7:30 PM-10:00 PM, Wednesday, 13 September 2006 Moscone Center -- Hall D, Poster

8:00 PM-10:00 PM, Monday, 11 September 2006 Moscone Center -- Hall D, Sci-Mix

Division of Physical Chemistry

The 232nd ACS National Meeting, San Francisco, CA, September 10-14, 2006