Sensitivity of the total beam profile distortion Z-scan for the measurement of nonlinear refraction

A comparison of the sensitivity of the recently proposed total beam profile distortion Z-scan to the well-known Z-scan and Eclipsing Z-scan techniques is presented. Experimental sensitivities are measured in the picosecond pulsed regime for studying Kerr nonlinearity in CS2 and in the cw-regime for studying thermal nonlinear refraction in an ethanol solution of malachite green. It is shown that the sensitivity of the new method is enhanced by more than one order of magnitude with respect to the usual Z-scan and more than five times with respect to the Eclipsing Z-scan.