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arXiv · 1204.0150

Intrinsic Structural Disorder and the Magnetic Ground State in Bulk EuTiO3

A. P. Petrovic·Y. Kato·S. S. Sunku·T. Ito·P. Sengupta·L. Spalek·M. Shimuta·T. Katsufuji·C. D. Batista·S. Saxena·C. Panagopoulos
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Abstract

The magnetic properties of single-crystal EuTiO3 are suggestive of nanoscale disorder below its cubic-tetragonal phase transition. We demonstrate that electric field cooling acts to restore monocrystallinity, thus confirming that emergent structural disorder is an intrinsic low-temperature property of this material. Using torque magnetometry, we deduce that tetragonal EuTiO3 enters an easy-axis antiferromagnetic phase at 5.6 K, with a first-order transition to an easy-plane ground state below 3 K. Our data is reproduced by a 3D anisotropic Heisenberg spin model.

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A. P. Petrovic, Y. Kato, S. S. Sunku, T. Ito, P. Sengupta, L. Spalek, M. Shimuta, T. Katsufuji, C. D. Batista, S. Saxena, C. Panagopoulos. 2012-04-01. Intrinsic Structural Disorder and the Magnetic Ground State in Bulk EuTiO3. https://doi.org/10.1103/physrevb.87.064103

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