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arXiv · 2311.14300

Observation of unconventional van der Waals multiferroics near room temperature

Yangliu Wu·Haipeng Lu·Xiaocang Han·Chendi Yang·Nanshu Liu·Xiaoxu Zhao·Liang Qiao·Wei Ji·Renchao Che·Longjiang Deng·Bo Peng
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Abstract

The search for two-dimensional (2D) van der Waals (vdW) multiferroics is an exciting yet challenging endeavor. Room-temperature 2D vdW few-layer multiferroic is a much bigger insurmountable obstacle. Here we report the discovery of an unconventional 2D vdW multiferroic with out-of-plane ferroelectric polarization and long-range magnetic orders in trilayer NiI2 device from 10 K to 295 K. The evolutions of magnetic domains with magnetic field, and the evolutions between ferroelectric and antiferroelectric phase have been unambiguously observed. More significantly, we realize a robust mutual control of magnetism and ferroelectricity at room temperature. The magnetic domains are manipulated by a small voltage ranging from 1 V to 6 V at 0 T and 295 K. This work opens opportunities for exploring multiferroic physics at the limit of few atomic layers.

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Yangliu Wu, Haipeng Lu, Xiaocang Han, Chendi Yang, Nanshu Liu, Xiaoxu Zhao, Liang Qiao, Wei Ji, Renchao Che, Longjiang Deng, Bo Peng. 2024-02-23. Observation of unconventional van der Waals multiferroics near room temperature. https://arxiv.org/abs/2311.14300

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