Modulation of the Dzyaloshinskii–Moriya interaction in Pt/Co/Pt with electric field induced strain
Shen Li, Suteng Zhao, Dion M. F. Hartmann, Wei Yang, Xiaoyang Lin, Weisheng Zhao, Reinoud Lavrijsen
Abstract
The modulation of the interfacial chiral magnetic exchange interaction, i.e., Dzyaloshinskii–Moriya interaction (DMI), is promising to realize ultralow-power information storage or logic devices. Recently, researchers used Brillouin light scattering to demonstrate that mechanical strain can be used to modulate the DMI in Pt/Co/Pt and switch its sign, i.e., the chirality. Toward practical storage applications, here, we utilize electric field-induced strain to modulate the DMI and measure it through asymmetric bubble expansion. The strain is generated by applying an electrical potential over a ferroelectric substrate PMN-PT [011] and then transferred to the ferromagnetic films above. The measurement results show that DMI in Pt/Co/Pt exhibits a butterfly-shaped curve following the strain variation as expected from PMN-PT [011]. The dependence of DMI on strain can be explained using the triatomic model based on the Fert-Levy theory. We find a significant DMI modulation between 0.09 and 0.29 mJ/m2; indeed, no sign switching is observed in our work, which we attribute to the initial state preparation of the film. This work provides a reference for future electric-field controlled ultralow-power spintronic devices.