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arXiv · 2006.15834

Electronic charge transfer driven by spin cycloidal structure

Y. Ishii·S. Horio·Y. Noda·M. Hiraishi·H. Okabe·M. Miyazaki·S. Takeshita·A. Koda·K. M. Kojima·R. Kadono·H. Sagayama·H. Nakao·Y. Murakami·H. Kimura
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Abstract

Muon spin rotation and resonant soft X-ray scattering experiments on prototype multiferroics RMn2O5 (R = Y, Sm) are used to demonstrate that the local electric displacements are driven by the spin-current (SC) mechanism. Small local electric displacements were evaluated by observing spin polarization at ligand O ions, for which implanted muons served as an extremely sensitive probe. Our results for YMn2O5 provide evidence that the spin polarization of O ions forming a spin cycloid chain with Mn spins increases in proportion to the vector spin chirality (Si x Sj ) of the Mn ions. This relationship strongly indicates that the charge transfer between O and Mn ions is driven by the SC mechanism, which leads to the ferroelectricity accompanying O spin polarization.

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Y. Ishii, S. Horio, Y. Noda, M. Hiraishi, H. Okabe, M. Miyazaki, S. Takeshita, A. Koda, K. M. Kojima, R. Kadono, H. Sagayama, H. Nakao, Y. Murakami, H. Kimura. 2020-06-29. Electronic charge transfer driven by spin cycloidal structure. https://doi.org/10.1103/physrevb.101.224436

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