Kerr effect as evidence of gyrotropic order in the cuprates - revisited
  Recent analysis has confirmed earlier general arguments that the Kerr response vanishes in any time-reversal invariant system which satisfies the Onsager relations. Thus, the widely cited relation between natural optical activity (gyrotropy) and the Kerr response, employed in Hosur \textit{et al}, Phys. Rev. B \textbf{87}, 115116 (2013), is incorrect. However, there is increasingly clear experimental evidence that, as argued in our paper, the onset of an observable Kerr-signal in the cuprates reflects point-group symmetry rather than time-reversal symmetry breaking. 
Pavan Hosur, A. Kapitulnik, S. A. Kivelson, J. Orenstein, S. Raghu, W.   Cho, A. Fried
cond-mat.supr-con cond-mat.str-el