Nonlinear refraction in CS_2 at 106 μm

Abstract
The nonlinear refractive index n2 of CS2 at 10.6 μm, the value of which is a subject of a recent controversy, is measured by an external self-focusing method. We found that n2 = (2.1 ± 0.7) × 10−11 esu, similar to the accepted value of n2 in the visible. Self-bending of spatially asymmetric CO2 laser beam in CS2 due to an ultrafast Kerr effect is observed, and the deduced value of n2 is in agreement with our results.