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arXiv · 2404.04383

Evidence for charge mediated coupling in Fe-Ga/PMN-PT composite multiferroic

M. Tortarolo·D. Goijman·M. A. Barral·S. Di Napoli·A. A. Pérez Martínez·G. Ramírez·A. Sarmiento·J. Gómez·A. Zakharova·S. E. Bayram·F. Stramaglia·C. A. F. Vaz·J. Milano·C. Piamonteze
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Abstract

We present an experimental study of the magnetoelectric coupling (MEC) in the Fe-Ga/PMN-PT thin film multiferroic composite by means of x-ray magnetic circular dichroism (XMCD) and ferromagnetic resonance (FMR). Our measurements show evidence for a charge mediated coupling mechanism, suggested by the asymmetric magnetic remanence (M$_{rem}$) behaviour under opposite electric fields ($\pm$ E) and the asymmetric resonance field (H$_r$) in the FMR measurements. Also, the FMR measurements reveal a perpendicular magnetic anisotropy (PMA), that can be related to an interface charge effect. and it is tunable by E field. Ab initio calculations support the existence of a charge mediated coupling at the Fe-Ga/PMN-PT interface.

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M. Tortarolo, D. Goijman, M. A. Barral, S. Di Napoli, A. A. Pérez Martínez, G. Ramírez, A. Sarmiento, J. Gómez, A. Zakharova, S. E. Bayram, F. Stramaglia, C. A. F. Vaz, J. Milano, C. Piamonteze. 2024-04-05. Evidence for charge mediated coupling in Fe-Ga/PMN-PT composite multiferroic. https://doi.org/10.1063/5.0243392

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