Z-scan measurement technique for non-Gaussian beams and arbitrary sample thicknesses

We demonstrate a new Z-scan measurement technique that permits the use of non-Gaussian beams and thick, as well as thin, samples. We expect that this technique will make possible the measurement of optical nonlinearities by the use of lasers that previously would have been unsuitable for this purpose, because of either inadequate beam quality or inadequate power. Another advantage of this technique is that it does not require detailed knowledge of the temporal characteristics of the laser pulse that is used.