Orbitally driven behaviour:: Mott transition, quantum oscillations and colossal magnetoresistance in bilayered Ca3Ru2O7 -: art. no. 159

We report recent transport and thermodynamic experiments over a wide range of temperatures for the Mott-like system Ca3Ru2O7 at high magnetic fields, B (less than or equal to30 T). This work reveals a rich and highly anisotropic phase diagram, where applying B along the a-, b-, and c-axis leads to vastly different behaviour. A fully spin-polarized state via a first-order metamagnetic transition is obtained for B greater than or equal to 6 T and Bparallel toa, and colossal magnetoresistance is seen for Bparallel tob, and quantum oscillations in the resistivity are observed for Bparallel toc, respectively. The interplay of the lattice, orbital and spin degrees of freedom are believed to give rise to this strongly anisotropic behaviour.