Evidence of superconductivity on the border of quasi-2D ferromagnetism in Ca2RuO4 at high pressure

Patricia L. Alireza; Fumihiko Nakamura; Swee K. Goh; Yoshiteru Maeno; Satoru Nakatsuji; Y. T. Chris Ko; Michael Sutherland; Stephen Julian; Gilbert G. Lonzarich

arXiv · 0912.1513

Evidence of superconductivity on the border of quasi-2D ferromagnetism in Ca2RuO4 at high pressure

Patricia L. Alireza·Fumihiko Nakamura·Swee K. Goh·Yoshiteru Maeno·Satoru Nakatsuji·Y. T. Chris Ko·Michael Sutherland·Stephen Julian·Gilbert G. Lonzarich

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Abstract

The layered perovskite Ca2RuO4 is a spin-one Mott insulator at ambient pressure and exhibits metallic ferromagnetism at least up to ~ 80 kbar with a maximum Curie temperature of 28 K. Above ~ 90 kbar and up to 140 kbar, the highest pressure reached, the resistivity and ac susceptibility show pronounced downturns below ~ 0.4 K in applied magnetic fields of up to ~10 mT. This indicates that our specimens of Ca2RuO4 are weakly superconducting on the border of a quasi-2D ferromagnetic state.

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Patricia L. Alireza, Fumihiko Nakamura, Swee K. Goh, Yoshiteru Maeno, Satoru Nakatsuji, Y. T. Chris Ko, Michael Sutherland, Stephen Julian, Gilbert G. Lonzarich. 2009-12-08. Evidence of superconductivity on the border of quasi-2D ferromagnetism in Ca2RuO4 at high pressure. https://arxiv.org/abs/0912.1513

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