Orbitally driven behaviour: Mott transition, quantum oscillations and colossal magnetoresistance in bilayered Ca3Ru2O7

We report recent transport and thermodynamic experiments over a wide range of temperatures for the Mott-like system Ca3Ru2O7 at high magnetic fields, B(⩽ 30 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 ⩾ 6 T and B‖a, and colossal magnetoresistance is seen for B‖b, and quantum oscillations in the resistivity are observed for B‖c, respectively. The interplay of the lattice, orbital and spin degrees of freedom are believed to give rise to this strongly anisotropic behaviour.