| One of the most interesting puzzles in the area of high temperature superconductors is the presence of "Fermi arcs" in photoemission experiments. These arcs evolve with increasing temperature from the nodes of the d-wave superconductor. In this manuscript, Alvarez and Dagotto describe a possible explanation of the Fermi arcs based on a state formed by superconducting clusters with sizes in a nanometer scale. The complex number phase of the superconducting order parameter is randomly distributed among the clusters and causes the Fermi arcs. Recent STM results by Yazdani and collaborators are compatible with the existence of such a state. Phys. Rev. Lett. 101, 177001 (2008). |