More Like this

1. Engineering of Ferroic Orders in Thin Films by Anionic Substitution

   https://doi.org/10.1002/adfm.202107135  

   Garcia‐Castro, Andres_Camilo; Ma, Yanjun; Romestan, Zachary; Bousquet, Eric; Cen, Cheng; Romero, Aldo_H (October 2021, Advanced Functional Materials)

   Abstract Multiferroics are a unique class of materials where magnetic and ferroelectric orders coexist. The research on multiferroics contributes significantly to the fundamental understanding of the strong correlations between different material degrees of freedom and provides an energy‐efficient route toward the electrical control of magnetism. While multiple ABO₃oxide perovskites are identified as being multiferroic, their magnetoelectric coupling strength is often weak, necessitating the material search in different compounds. Here, the observation of room‐temperature multiferroic orders in multi‐anion SrNbO_3−xN_xthin films is reported. In these samples, the multi‐anion state enables the room‐temperature ferromagnetic ordering of the Nb d‐electrons. Simultaneously, ferroelectric responses that originate from the structural symmetry breaking associated are found with both the off‐center displacements of Nb and the geometric displacements of Sr, depending on the relative O‐N arrangements within the Nb‐centered octahedra. The findings not only diversify the available multiferroic material pool but also demonstrate a new multiferroism design strategy via multi‐anion engineering. 

   more » « less
2. Domain-wall magnetoelectric coupling in multiferroic hexagonal YbFeO3 films

   https://doi.org/10.1038/s41598-023-28365-x  

   Li, Xin; Yun, Yu; Thind, Arashdeep Singh; Yin, Yuewei; Li, Qiang; Wang, Wenbin; N’Diaye, Alpha T.; Mellinger, Corbyn; Jiang, Xuanyuan; Mishra, Rohan; et al (January 2023, Scientific Reports)

   Abstract Electrical modulation of magnetic states in single-phase multiferroic materials, using domain-wall magnetoelectric (ME) coupling, can be enhanced substantially by controlling the population density of the ferroelectric (FE) domain walls during polarization switching. In this work, we investigate the domain-wall ME coupling in multiferroic h-YbFeO₃thin films, in which the FE domain walls induce clamped antiferromagnetic (AFM) domain walls with reduced magnetization magnitude. Simulation according to the phenomenological theory indicates that the domain-wall ME effect is dramatically enhanced when the separation between the FE domain walls shrinks below the characteristic width of the clamped AFM domain walls during the ferroelectric switching. Experimentally, we show that while the magnetization magnitude remains same for both the positive and the negative saturation polarization states, there is evidence of magnetization reduction at the coercive voltages. These results suggest that the domain-wall ME effect is viable for electrical control of magnetization. 

   more » « less
3. Discovery of a layered multiferroic compound Cu _1−x Mn _1+y SiTe ₃ with strong magnetoelectric coupling

   https://doi.org/10.1126/sciadv.adp9379  

   De, Chandan; Liu, Yu; Ayyagari, Sai_Venkata Gayathri; Zheng, Boyang; Kelley, Kyle P; Hazra, Sankalpa; He, Jingyang; Pawledzio, Sylwia; Mali, Subin; Guchhait, Samaresh; et al (January 2025, Science Advances)

   Multiferroic materials host both ferroelectricity and magnetism, offering potential for magnetic memory and spin transistor applications. Here, we report a multiferroic chalcogenide semiconductor Cu_1−xMn_1+ySiTe₃(0.04 ≤x≤ 0.26; 0.03 ≤y≤ 0.15), which crystallizes in a polar monoclinic structure (Pmspace group). It exhibits a canted antiferromagnetic state below 35 kelvin, with magnetic hysteresis and remanent magnetization under 15 kelvin. We demonstrate multiferroicity and strong magnetoelectric coupling through magnetodielectric and magnetocurrent measurements. At 10 kelvin, the magnetically induced electric polarization reaches ~0.8 microcoulombs per square centimeter, comparable to the highest value in oxide multiferroics. We also observe possible room-temperature ferroelectricity. Given that multiferroicity is very rare among transition metal chalcogenides, our finding sets up a unique materials platform for designing multiferroic chalcogenides. 

   more » « less
4. Room temperature ferroelectricity and self-biased magnetoelectricity in SmFeO3 nanocomposite by 3D strain engineering

   https://doi.org/10.1063/5.0279174  

   Bansal, Manisha; Keeney, Lynette; Choudhury, Abhijeet; Huang, Jialong; Wang, Haiyan; MacManus-Driscoll, Judith L; Maity, Tuhin (September 2025, APL Electronic Devices)

   Tuning spin and charge degrees of freedom of complex oxide materials can enable significant advancements in future spintronics. In this study, by three dimensional strain engineering, we demonstrate room temperature ferroelectricity and magnetoelectricity in a vertically aligned nanocomposite thin film structure, composed of vertical nanopillars of SmFeO3 (SFO) embedded within the NiFeO4 (NFO) matrix. A three-dimensional tensile strain is induced in the SFO as a result of the unique film architecture. The tensile strain in SFO produces strong room temperature ferroelectric response instead of the normally very weak ferroelectricity of unstrained SFO, which is an improper ferroelectric. The induced ferroelectricity in SFO enables self-biased magnetoelectric coupling to be achieved between the two phases (magnetoelectric coupling coefficient ∼4 × 10−11 sm−1 at room temperature). The magnetoelectric coupling is facilitated by strain transfer across the vertical interfaces of the two phases. We additionally observe an exchange bias of ∼200 Oe (at 2 K) surviving up to the room temperature, indicating strongly coupled interfaces of SFO and NFO. These findings represent a step forward in future magnetoelectric RAM devices. 

   more » « less
5. Electric-field control of skyrmions in multiferroic heterostructure via magnetoelectric coupling

   https://doi.org/10.1038/s41467-020-20528-y  

   Ba, You; Zhuang, Shihao; Zhang, Yike; Wang, Yutong; Gao, Yang; Zhou, Hengan; Chen, Mingfeng; Sun, Weideng; Liu, Quan; Chai, Guozhi; et al (December 2021, Nature Communications)

   null (Ed.)

   Abstract Room-temperature skyrmions in magnetic multilayers are considered to be promising candidates for the next-generation spintronic devices. Several approaches have been developed to control skyrmions, but they either cause significant heat dissipation or require ultrahigh electric fields near the breakdown threshold. Here, we demonstrate electric-field control of skyrmions through strain-mediated magnetoelectric coupling in ferromagnetic/ferroelectric multiferroic heterostructures. We show the process of non-volatile creation of multiple skyrmions, reversible deformation and annihilation of a single skyrmion by performing magnetic force microscopy with in situ electric fields. Strain-induced changes in perpendicular magnetic anisotropy and interfacial Dzyaloshinskii–Moriya interaction strength are characterized experimentally. These experimental results, together with micromagnetic simulations, demonstrate that strain-mediated magnetoelectric coupling (via strain-induced changes in both the perpendicular magnetic anisotropy and interfacial Dzyaloshinskii–Moriya interaction is responsible for the observed electric-field control of skyrmions. Our work provides a platform to investigate electric-field control of skyrmions in multiferroic heterostructures and paves the way towards more energy-efficient skyrmion-based spintronics. 

   more » « less