Comment on "Superinsulator and Quantum Synchronization"

We show that the “theory” of “superinsulating” state presented by V.Vinokur et al (Nature vol. 452, p. 613, 2008) and Fistul et al (Phys. Rev. Lett. vol. 100, 086805, 2008) is essentially incorrect due to a sequence of errors in the theoretical analysis of the standard model of Josephson arrays which properties have been carefully studied and described in the literature. The line of calculations suggested in these articles lead to unphysical results. In particular, the calculations predict a direct current flowing through a capacitor. Moreover, this current may flow even in the absence of voltage - a sort of supercurrent flowing in the “superinsulating” state. We also question that the theoretical model employed in these works, even if treated correctly, is applicable to the analysis of experimental data on homogeneously disordered superconductive films.