Using Dipole Interaction to Achieve Nonvolatile Voltage Control of Magnetism in Multiferroic Heterostructures

• Published in: Advanced materials (Weinheim) 2021-12, Vol.33 (52), p.e2105902-n/a
• Main Authors: Chen, Aitian, Piao, Hong‐Guang, Ji, Minhui, Fang, Bin, Wen, Yan, Ma, Yinchang, Li, Peisen, Zhang, Xi‐Xiang
• Format: Article
• Language: English
• Subjects: Dipole interactions; Electric potential; Electrical junctions; Ferroelectricity; Heterostructures; magnetic tunnel junctions; Magnetism; Magnetization; Magnets; Materials science; multiferroic heterostructures; Multiferroic materials; nonvolatile voltage control of magnetism; strain‐mediated magnetoelectric coupling; Substrates; Tunnel junctions; Voltage
• ISSN: 0935-9648; 1521-4095; 1521-4095
• DOI: 10.1002/adma.202105902

Nonvolatile electrical control of magnetism is crucial for developing energy‐efficient magnetic memory. Based on strain‐mediated magnetoelectric coupling, a multiferroic heterostructure containing an isolated magnet requires nonvolatile strain to achieve this control. However, the magnetization response of an interacting magnet to strain remains elusive. Herein, Co/MgO/CoFeB magnetic tunnel junctions (MTJs) exhibiting dipole interaction on ferroelectric substrates are fabricated. Remarkably, nonvolatile voltage control of the resistance in the MTJs is demonstrated, which originates from the nonvolatile magnetization rotation of an interacting CoFeB magnet driven by volatile voltage‐generated strain. Conversely, for an isolated CoFeB magnet, this volatile strain induces volatile control of magnetism. These results reveal that the magnetization response to volatile strain among interacting magnets is different from that among isolated magnets. The findings highlight the role of dipole interaction in multiferroic heterostructures and can stimulate future research on nonvolatile electrical control of magnetism with additional interactions. A new strategy using the dipole interaction to achieve nonvolatile electrical control of magnetism is demonstrated in an interacting magnet using a volatile strain. This work reveals the important role of the dipole interaction in multiferroic heterostructures and can stimulate future research on the electrical control of magnetism by introducing additional interactions to multiferroic heterostructures.