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arXiv · 1403.5136

Reversing ferroelectric polarization in multiferroic DyMn2O5 by nonmagnetic Al substitution of Mn

Z. Y. Zhao·M. F. Liu·X. Li·J. X. Wang·Z. B. Yan·K. F. Wang·J. -M. Liu
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Abstract

The multiferroic RMn2O5 family, where R is rare-earth ion or Y, exhibits rich physics of multiferroicity which has not yet well understood, noting that multiferroicity is receiving attentions for promising application potentials. DyMn2O5 is a representative member of this family. The ferroelectric polarization in DyMn2O5 is claimed to have two anti-parallel components: one (PDM) from the symmetric exchange striction between the Dy3+-Mn4+ interactions and the other (PMM) from the symmetric exchange striction between the Mn3+-Mn4+ interactions. We investigate the evolutions of the two components upon a partial substitution of Mn3+ by nonmagnetic Al3+ in order to tailor the Mn-Mn interactions and then to modulate component PMM in DyMn2-x/2Alx/2O5. It is revealed that the ferroelectric polarization can be successfully reversed by the Al-substitution via substantially suppressing the Mn3+-Mn4+ interactions and thus the PMM. The Dy3+-Mn4+ interactions and the polarization component PDM can sustain against the substitution until a level as high as x=0.2. In addition, the independent Dy spin ordering is shifted remarkably down to an extremely low temperature due to the Al3+ substitution. The present work not only confirms the existence of the two anti-parallel polarization components but also unveils the possibility of tailoring them independently.

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Z. Y. Zhao, M. F. Liu, X. Li, J. X. Wang, Z. B. Yan, K. F. Wang, J. -M. Liu. 2014-03-20. Reversing ferroelectric polarization in multiferroic DyMn2O5 by nonmagnetic Al substitution of Mn. https://doi.org/10.1063/1.4891979

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