Charge transfer and hybrid ferroelectricity in (YFeO$_{3}$)$_{n}$/(YTiO$_{3}$)$_{n}$ magnetic superlattices

Huimin Zhang; Yakui Weng; Xiaoyan Yao; Shuai Dong

doi:10.1103/physrevb.91.195145

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arXiv · 1505.05978

Charge transfer and hybrid ferroelectricity in (YFeO$_{3}$)$_{n}$/(YTiO$_{3}$)$_{n}$ magnetic superlattices

Huimin Zhang·Yakui Weng·Xiaoyan Yao·Shuai Dong

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Abstract

Interfaces in oxide heterostructures always provide a fertile ground for emergent properties. Charge transfer from a high energy band to a low energy opponent is naturally expected, as occurring in semiconductor $p$-$n$ junctions. In this study, several exceptional physical phenomena have been predicted in (YFeO$_3$)$_n$/(YTiO$_3$)$_n$ superlattices. First, the charge transfer between these Mott insulators is in opposite to the intuitive band alignment scenario. Second, hybrid ferroelectricity with a moderate polarization is generated in the $n=2$ magnetic superlattice. Furthermore, the ferroelectric-type distortion can persist even if the ($AB$O$_3$)$_2$/($AB$'O$_3$)$_2$ system turns to be metallic, rending possible metallic ferroelectricity.

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Huimin Zhang, Yakui Weng, Xiaoyan Yao, Shuai Dong. 2015-05-22. Charge transfer and hybrid ferroelectricity in (YFeO$_{3}$)$_{n}$/(YTiO$_{3}$)$_{n}$ magnetic superlattices. https://doi.org/10.1103/physrevb.91.195145

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