Experimental evidence of third-order nonlinear dichroism in a liquid of chiral molecules

We present experimental evidence of the existence of a nonlinear circular dichroism in a liquid of chiral molecules. This effect is demonstrated by a light-induced circular dichroism on two enantiomeric RuTB [ruthenium(II) tris(bipyridyl)] samples after a careful analysis of the impact of the third-order nonlinear response on the optical activity of the system. These experimental results are in good agreement with a previous theoretical investigation.