Charge density wave instability in holographic d-wave superconductor

We report the observation of the spatially modulated static mode in the spectrum of fluctuations around the condensed phase of the holographic d-wave superconductor. The mode involves the time component of the gauge field that is related to the charge density wave in the dual superconductor. No additional ingredients are added to the action of five dimensional theory. We speculate on the relevance of the observed mode to the formation of the pseudogap state.