Localized electronic states and photoemission superconducting condensate   in Bi$_{2}$Sr$_{2}$Ca$_{1}$Cu$_{2}$O$_{8+x}$
  We present the first detailed angle-resolved photoemission evidence that there are two types of carriers that contribute to the photoemission superconducting condensate in $Bi_{2}Sr_{2}Ca_{1}Cu_{2}O_{8+x}$. Our data indicate that both itinerant and somewhat localized normal state carriers can contribute to the formation of Cooper pairs. 
Jian Ma, C.Quitmann, R.J.Kelley, G. Margaritondo, and M.Onellion (Dept   of Phys. & Applied Superconductivity Center, UW-Mad...