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arXiv · 1003.2068

Anomalous pressure effect on the magnetic ordering in multiferroic BiMnO3

C. C. Chou·S. Taran·J. L. Her·C. P. Sun·C. L. Huang·H. Sakurai·A. A. Belik·E. Takayama-Muromachi·H. D. Yang
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Abstract

We report the magnetic field dependent dc magnetization and the pressure-dependent (pmax ~ 16 kbar) ac susceptibilities Xp(T) on both powder and bulk multiferroic BiMnO3 samples, synthesized in different batches under high pressure. A clear ferromagnetic (FM) transition is observed at TC ~ 100 K, and increases with magnetic field. The magnetic hysteresis behavior is similar to that of a soft ferromagnet. Ac susceptibility data indicate that both the FM peak and its temperature (TC) decrease simultaneously with increasing pressure. Interestingly, above a certain pressure (9 ~ 11 kbar), another peak appears at Tp ~ 93 K, which also decreases with increasing pressure, with both these peaks persisting over some intermediate pressure range (9 ~ 13 kbar). The FM peak disappears with further application of pressure; however, the second peak survives until present pressure limit (pmax ~ 16 kbar). These features are considered to originate from the complex interplay of the magnetic and orbital structure of BiMnO3 being affected by pressure.

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C. C. Chou, S. Taran, J. L. Her, C. P. Sun, C. L. Huang, H. Sakurai, A. A. Belik, E. Takayama-Muromachi, H. D. Yang. 2010-03-10. Anomalous pressure effect on the magnetic ordering in multiferroic BiMnO3. https://doi.org/10.1103/physrevb.78.092404

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