Beam waist changes in lithium niobate during Z-scan measurement

The nonlinear propagation of Gaussian beams in LiNbO3 has been investigated using the Z-scan technique. Experimental results shown that the minimum beam waist has been broadened. The third-order optical nonlinearity χ(3) of LiNbO3 has been measured at 514 nm and found for the real and imaginary parts of the nonlinearity to be −1.7×10−5 and −4.3×10−6 esu, respectively.