Search results for "non-linear vibrational microscopy"

Background-free nonlinear Raman microscopy and spectroscopy at interfaces

2010

Gaussian focused beams exhibit specific properties that drive the emitted fields in nonlinear optical microscopy. We discuss here how the basic field and object symmetry properties can be favorably used to obtain background-free images and spectra in third-order nonlinear optical processes. We concentrate here on coherent anti-Stokes Raman scattering (CARS), the non-linear analogue of Raman scattering. In CARS microscopy, the vibrational related (“resonant”) signal is often overwhelmed by an electronic related (“nonresonant”) background. Various strategies have been implemented to circumvent the undesirable effects of this nonresonant background: picosecond pulse excitation, time resolved, …