Pulse shaping strategies for nonlinear interferometric vibrational imaging optimized for biomolecular imaging

Nonlinear interferometric vibrational imaging (NIVI) measures the temporal cross-correlation of anti-Stokes radiation from coherent anti-Stokes Raman scattering (CARS) processes to achieve increased sensitivity, stray light rejection, and nonresonant background rejection. Because the intensity of CARS radiation is proportional to the square of the molecular density of a target resonance, it is critical to maximize the recoverable signal for a given illumination level. Especially if one desires to measure several resonances, there can be a sensitivity as well as a speed advantage to measuring them simultaneously rather than serially. We discuss the methods of sample excitation that NIVI allows and their potential sensitivity advantages, as well as present experimental results demonstrating Raman signal recovery using these pulse sequences.