Measurements of the GVD of water and methanol and laser pulse characterization using direct imaging methods

We report experimental values of the group velocity dispersion (GVD) of water and methanol at 800 nm. We find GVD800water= (25.71 ± 0.5) fs 2 mm-1 and GVD800methanol=(33.56 ±0.5) fs2 mm-1. These were measured by sending 50 fs, 800 nm pulses with various amounts of chirp through a glass cell filled with a solution of fluorescein in these solvents and recording the production of visible light from the side using a commercial digital camera. This simple setup also gives quantitative information on the duration of our pulses and lets us check independently the correct operation of our grating-based pulse compressor. Results are compared to FROG measurements.