Undulation instability of a planar S*c liquid crystal in the presence of dilation strains

Abstract
Due to sample dilations above a threshold value an undulation instability was found in a planar S*c of the commercially available thermochromic liquid crystal CE3. Contrary to the SA practice no instability was found in the homeotropic alignment of the S* c phase. Preliminary but detailed experimental results and a simple phenomelogical explanation are presented