Fully automatic Z-scan setup for determining the nonlinear optical properties

Fully automatic Z-scan setup for determining the nonlinear optical properties

Z-scan technique has been widely exploited as an accurate and reliable method for determining the nonlinear refractive index and nonlinear absorption coefficient. In this technique a sample is scanned along the propagation direction of a focused laser beam while the power transmitted through the sample (an aperture) is measured as function of the sample position. We report on a fully automatic Z-scan setup by which the nonlinear absorption coefficient (refractive index) can be determined by a one-click home-made LabVIEW program. This program handles the movement of the sample mounted on a motorized translation stage, perform the data acquisition from a Pico-scope connected to a pair of photodiodes, normalizes the transmittance data, accomplishes the fitting process to extract the required quantities, reports the extracted parameters and finally sends the entire data to Origin software for further process such as plotting and drawing the required figures.