Journal Article

Bulk Dzyaloshinskii–Moriya interaction in amorphous ferrimagnetic alloys

Yoshikawa Hiroki, Kurata Hiroki, Dae-Yun, Kim, Hirata Yuushou, Ham Wooseung, Haruta Mitsutaka, Hyeon-Jong, Park, Kim, Sanghoon, Go Gyungchoon, Moriyama Takahiro, Sug-Bong, Choe, Duck-Ho, Kim, Kyung-Jin, Lee, Ko Hye-Won, Futakawa Yasuhiro, Ono Teruo, Okuno Takaya, Nishimura Tomoe, Tsukamoto Arata, Shiota Yoichi

2019

Overview

Symmetry breaking is a fundamental concept that prevails in many branches of physics1–5. In magnetic materials, broken inversion symmetry induces the Dzyaloshinskii–Moriya interaction (DMI), which results in fascinating physical behaviours6–14 with the potential for application in future spintronic devices15–17. Here, we report the observation of a bulk DMI in GdFeCo amorphous ferrimagnets. The DMI is found to increase linearly with an increasing thickness of the ferrimagnetic layer, which is a clear signature of the bulk nature of DMI. We also found that the DMI is independent of the interface between the heavy metal and ferrimagnetic layer. This bulk DMI is attributed to an asymmetric distribution of the elemental content in the GdFeCo layer, with spatial inversion symmetry broken throughout the layer. We expect that our experimental identification of a bulk DMI will open up additional possibilities to exploit this interaction in a wide range of materials.A composition gradient is found to provide the necessary structural inversion asymmetry for a bulk Dzyaloshinskii–Moriya interaction to manifest itself.

• Publisher: Nature Publishing Group
• Subject: Amorphous alloys / Broken symmetry / Ferrimagnetism / Ferrimagnets / Heavy metals / Magnetic materials / Skewed distributions / Symmetry / Thickness