Considerations about Z-scan sensitivity improvement: theory versus experiments

Abstract : This paper reports an experimental demonstration of the improvement of the Z-scan technique's sensitivity. It is shown that this sensitivity can be multiplied by a factor equal to almost 400 with the help of simple binary diffractive elements. Such a possibility was actually predicted theoretically in one of our previous papers. In this study, the interpretation is investigated in a wider context taking into account the definition of the signal normalisation as introduced by Z-scan and the well-known eclipsing Z-scan (EZ-scan) experiments. In particular, advantages and drawbacks are compared, by looking at the normalised or the unnormalised aperture transmission.