Large-Voltage Tuning of Dzyaloshinskii–Moriya Interactions: A Route toward Dynamic Control of Skyrmion Chirality

• Published in: Nano letters Vol. 18; no. 8; pp. 4871 - 4877
• Main Authors: Srivastava, Titiksha, Schott, Marine, Juge, Roméo, Křižáková, Viola, Belmeguenai, Mohamed, Roussigné, Yves, Bernand-Mantel, Anne, Ranno, Laurent, Pizzini, Stefania, Chérif, Salim-Mourad, Stashkevich, Andrey, Auffret, Stéphane, Boulle, Olivier, Gaudin, Gilles, Chshiev, Mairbek, Baraduc, Claire, Béa, Hélène
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 08.08.2018
• Subjects: Condensed Matter; Electronics; Engineering Sciences; Materials Science; Physics; skyrmions; Dzyaloshinskii−Moriya interaction; chirality; perpendicular magnetic anisotropy; electric field effects
• ISSN: 1530-6984; 1530-6992
• DOI: 10.1021/acs.nanolett.8b01502

Electric control of magnetism is a prerequisite for efficient and low-power spintronic devices. More specifically, in heavy metal–ferromagnet–insulator heterostructures, voltage gating has been shown to locally and dynamically tune magnetic properties such as interface anisotropy and saturation magnetization. However, its effect on interfacial Dzyaloshinskii–Moriya Interaction (DMI), which is crucial for the stability of magnetic skyrmions, has been challenging to achieve and has not been reported yet for ultrathin films. Here, we demonstrate a 130% variation of DMI with electric field in Ta/FeCoB/TaO x trilayer through Brillouin Light Spectroscopy (BLS). Using polar magneto-optical Kerr-effect microscopy, we further show a monotonic variation of DMI and skyrmionic bubble size with electric field with an unprecedented efficiency. We anticipate through our observations that a sign reversal of DMI with an electric field is possible, leading to a chirality switch. This dynamic manipulation of DMI establishes an additional degree of control to engineer programmable skyrmion-based memory or logic devices.