Measuring the GVD of transparent solvents and creation of laser-etched holographic mirrors

We report experimental values of the group velocity dispersion (GVD) of water and methanol at 800 nm. These values were measured by sending 50-fs, 800-nm pulses with various amounts of chirp through a cell filled with a solution of fluorescein in these solvents and recording the production of visible 2-photon fluorescence light using a commercial digital camera. This simple setup also gives information on the duration of our pulses and has allowed us to identify behavior consistent with the presence of third-order spectral phase in the pulse. Additionally, we introduce a simple and practical method[1] to create ultrashort, intense optical vortices (`donut modes') for applications using high-intensity lasers. A laser-etching process is used to encode a holographic grating onto laser-quality gold mirrors, which can withstand intensities of up to $10^{12}\mbox{W/cm}^2$. With new methods for angular dispersion compensation[2], optical vortices can be produced with intensities $\sim 10^{11}\mbox{W/cm}^2$. [1] Strohaber J, Scarborough T, and Uiterwaal C J G J \textit{Appl. Opt.} \textbf{46} 8583 (2007) [2] Strohaber J, Petersen C, and Uiterwaal C J G J \textit{Opt. Lett.} \textbf{32} 2387 (2007)