The nonlinear Goos-Hanchen effect is experimentally isolated for the t
otal reflection of a Gaussian beam at an interface between a linear me
dium and a negative Kerr-type nonlinear medium. The evolution of this
nonlinear spatial shift versus light intensity is measured for both TE
and TM polarizations. The results are in good agreement with a simple
model based on nonlinear Artmann's formulas.