Fermi Arcs in a Doped Pseudospin-1/2 Heisenberg Antiferromagnet
  High temperature superconductivity in cuprates arises from an electronic state that remains poorly understood. We report the observation of a related electronic state in a non-cuprate material Sr2IrO4 in which the unique cuprate Fermiology is largely reproduced. Upon surface electron doping through in situ deposition of alkali-metal atoms, angle-resolved photoemission spectra of Sr2IrO4 display disconnected segments of zero-energy states, known as Fermi arcs, and a gap as large as 80 meV. Its evolution toward a normal metal phase with a closed Fermi surface as a function of doping and temperature parallels that in the cuprates. Our result suggests that Sr2IrO4 is a useful model system for comparison to the cuprates. 
Y. K. Kim, O. Krupin, J. D. Denlinger, A. Bostwick, E. Rotenberg, Q.   Zhao, J. F. Mitchell, J. W. Allen, and B. J. Kim
cond-mat.str-el cond-mat.supr-con