Chemically selective imaging by spectral phase shaping for broadband CARS around 3000 cm^−1

Abstract

Chemically selective microscopy based on broadband coherent anti-Stokes Raman scattering (CARS) is demonstrated on a mixed sample of 4 m diameter polystyrene (PS) and poly (methyl methacrylate) (PMMA) beads. The CARS signal from the PS or the PMMA beads is enhanced or suppressed, depending on the phase profile applied to the broadband spectrum. Using a combination of negative and positive (sloped)-phase steps the purely nonresonant background signal is removed.

Phase aspects of (broadband) stimulated Raman scattering

“…for simple detection that in turn allows for high-speed imaging (van Rhijn et al 2009 ). Other schemes can be created (Oron et al 2004, McGrane et al 2009 ) where a larger response is generated in a limited part of the spectrum.…”

Investigation of adaptive laser pulse shaping by direct estimation of group delay profile

“…Details of the process, the optimization, and numerical considerations have been reported elsewhere [32][33][34]. In brief, we study a CARS process with a broadband shaped femtosecond laser pulse centered at 800 nm with a bandwidth of 25.6 nm, and a narrowband Stokes pulse centered at 1064 nm and a bandwidth negligible compared to that of the pump (=probe) beam.…”

Tailoring a coherent control solution landscape by linear transforms of spectral phase basis

“…An alternative approach is to traverse the landscape by applying well-known phase profiles to the input laser pulse and scan one or more parameters. In addition to such open-loop scans [4][5][6], an adaptive scheme is often employed to find the optimal phase profile by relying on the computational intelligence of an evolutionary algorithm [7][8][9][10][11][12].…”