Filling Control of the Pyrochlore Oxide Y2Ir2O7
  We report the filling control of the pyrochlore oxide Y2Ir2O7. Metallic ground state appears with increasing substitution content x (x >= 0.3). We have revealed that the density of states at the Fermi level rapidly changes with x by this filling control of Y2Ir2O7. 
Hideto Fukazawa and Yoshiteru Maeno (Kyoto Univ., Japan)