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arXiv · 2006.16080

Domain switching and exchange bias control by electric field in multiferroic conical magnet Mn$_2$GeO$_4$

Jonas K. H. Fischer·Hiroki Ueda·Tsuyoshi Kimura
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Abstract

The electric field effect on magnetism was examined in the multiferroic conical magnet Mn$_2$GeO$_4$, which shows a strong coupling between ferromagnetic and ferroelectric order parameters. The systematic evaluation of the electric polarization in the multiferroic phase below 5.5 K under various field cooling conditions reveals that small magnetic fields of 0.1 T significantly reduce the required electric fields needed to reach saturation. By applying electric fields during magnetic field dependent hysteresis measurements of magnetization M and polarization P an electrically controllable exchange bias was observed, a phenomenon exceedingly rare in single phase multiferroics. Furthermore, non-reversible electric switching of P and M domains was achieved under specific magnetic field conditions.

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Jonas K. H. Fischer, Hiroki Ueda, Tsuyoshi Kimura. 2020-06-29. Domain switching and exchange bias control by electric field in multiferroic conical magnet Mn$_2$GeO$_4$. https://doi.org/10.1103/physrevb.102.054412

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