From Mott insulator to ferromagnetic metal: a pressure study of Ca${}_2$RuO${}_4$

Abstract

We show that the pressure-temperature phase diagram of the Mott insulator Ca${}_2$RuO${}_4$ features a metal-insulator transition at 0.5GPa: at 300K from paramagnetic insulator to paramagnetic quasi-two-dimensional metal; at $T\le$ 12K from antiferromagnetic insulator to ferromagnetic, highly anisotropic, three-dimensional metal. % We compare the metallic state to that of the structurally related p-wave superconductor Sr${}_2$RuO${}_4$, and discuss the importance of structural distortions, which are expected to couple strongly to pressure.

4 pages, 4figures