Non-dispersive Fermi arcs and absence of charge ordering in the   pseudogap phase of Bi2Sr2CaCu2O8+d
  The autocorrelation of angle resolved photoemission data from the high temperature superconductor Bi2Sr2CaCu2O8+d shows distinct peaks in momentum space which disperse with binding energy in the superconducting state, but not in the pseudogap phase. Although it is tempting to attribute a non-dispersive behavior in momentum space to some ordering phenomenon, a de-construction of the autocorrelation reveals that the non-dispersive peaks arise not from ordering, but rather from the tips of the Fermi arcs, which themselves do not change with binding energy. 
U. Chatterjee, M. Shi, A. Kaminski, A. Kanigel, H. M. Fretwell, K.   Terashima, T. Takahashi, S. Rosenkranz, Z. Z. Li, H. Ra...