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From Mott insulator to ferromagnetic metal: a pressure study of Ca$_{2}$RuO$_{4}$

Fumihiko Nakamura·Tatsuo Goko·Masakazu Ito·Toshizo Fujita·Satoru Nakatsuji·Hideto Fukazawa·Yoshiteru Maeno·Patricia Alireza·Dominic Forsythe·Stephen R. Julian
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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 $T \leq$ 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.

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Fumihiko Nakamura, Tatsuo Goko, Masakazu Ito, Toshizo Fujita, Satoru Nakatsuji, Hideto Fukazawa, Yoshiteru Maeno, Patricia Alireza, Dominic Forsythe, Stephen R. Julian. 2002-03-12. From Mott insulator to ferromagnetic metal: a pressure study of Ca$_{2}$RuO$_{4}$. https://doi.org/10.1103/physrevb.65.220402

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