  It is known that time-dependent perturbations can enhance superconductivity
and increase the critical temperature. If this phenomenon happens to high-T_c
superconductors, one could obtain room-temperature superconductors, but this is
still an open issue experimentally. Meanwhile, we would like to understand this
phenomenon from gravity dual and see if the enhancement is possible for
holographic superconductors. Previous work (arXiv:1104.4098 [hep-th]) has
studied this issue by adding a "time-dependent chemical potential," but their
analysis is questionable as a true dynamic equilibrium. In particular, the AdS
boundary does not supply energy to the bulk spacetime in their setup. A more
appropriate way to discuss the enhancement is to add a time-dependent vector
potential, i.e., a time-dependent electric field. However, the enhancement does
not occur for holographic superconductors.
