Competition between superconductivity and nematic order : anisotropy of   superconducting coherence length
  We study the interplay between nematic order and superconductivity, motivated by a recent experiment on FeSe observing strongly distorted vortex shapes (Song et al., Science 332, 1410 (2011)). We show that the nematic order strongly enhances the anisotropy in the superconducting coherence length, beyond that expected from considerations of the Ginzburg-Landau theory. We obtain universal functions describing the coupling between the nematic order and superconductivity, and discuss connections of our results to the experiments. 
Eun Gook Moon and Subir Sachdev
cond-mat.str-el