Tunneling magnetoresistance and quantum oscillations in bilayered Ca3Ru2O7 -: art. no. 060406

We report the interplane resistivity, rho(c), at high magnetic fields B, with different orientations together with structural and magnetic properties of bilayered Ca3Ru2O7, a Mott-like system with a gap of 0.1 eV. A wide array of conventionally unanticipated phenomena revealed in this work includes (1) a collapse of the c-axis lattice parameter at a metal-nonmetal transition, (2) quantum oscillations in rho(c) in the gapped, nonmetallic state for the Bparallel toc axis, (3) interplane tunneling magnetoresistivity for the Bparallel toa or b axis, and yet conspicuously different anisotropies of the colossal magnetoresistivity and magnetization, and (4) a non-Fermi-liquid behavior in a metallic state fully recovered in high magnetic fields. The implications of the coexistence of these conflicting phenomena are discussed.