GQ-08 Temperature Dependence of Dzyaloshinskii-Moriya Interaction in Pt/Co/Gd Thin Films
Creators: Fei Wei
Yang Zhou
Wenjun Zhang and Shishou Kang
Publisher: name: IEEE
Year: 2025

Magnetic skyrmions generated in an antiferromagnetically (AFM) coupled system have attracted considerable interest and offer potential advantages for spintronic devices. Due to negligible dipolar fields, these skyrmions enable reduced skyrmion-Hall effects and smaller skyrmion sizes for ultra-high-density information storage. However, the Dzyaloshinskii-Moriya interaction (DMI) is a crucial factor in such materials, determining the stability and dynamic characteristics of chiral spin structures like skyrmions. Here, we focus on a Pt/Co/Gd trilayer thin film system with AFM coupling and investigate the temperature dependence of DMI using a wavevector-resolved Brillouin light scattering (BLS) spectrometer. Fig. 1a illustrates the magnetization of Pt(4 nm)/Co(1 nm)/Gd(2 nm) films. Due to the AFM coupling between Co and Gd layers, the total magnetization decreases with decreasing temperature. The compensation temperature, where the total magnetization exhibits a minimum value, is around 50K. As the temperature further decreases, the total magnetization starts to increase as the magnetization of Gd increases more rapidly compared to that of Co. Fig. 1b shows the temperature dependence of interfacial DMI in the Pt(4 nm)/Co(1 nm)/Gd(2 nm) film. It is clear that the interfacial DMI intensity initially increases with decreasing temperature, peaking at around 45K with a maximum value of approximately 3.21 mJ/m2. We further clarify that this behavior is strongly related to the temperature-driven perpendicular anisotropy in this system by anomalous Hall effect (AHE) measurements. Moreover, our results can qualitatively explain the observed most stable skyrmions in Co/Gd/Pt multilayers at the low temperature of 70K[1].References: [1] X. Wang et al., Phys. Rev. Mater. 6, 084412 (2022).
Magnetic skyrmions generated in an antiferromagnetically (AFM) coupled system have attracted considerable interest and offer potential advantages for spintronic devices. Due to negligible dipolar fields, these skyrmions enable reduced skyrmion-Hall effects and smaller skyrmion sizes for ultra-high-density information storage. However, the Dzyaloshinskii-Moriya interaction (DMI) is a crucial factor in such materials, determining the stability and dynamic characteristics of chiral spin structures like skyrmions. Here, we focus on a Pt/Co/Gd trilayer thin film system with AFM coupling and investigate the temperature dependence of DMI using a wavevector-resolved Brillouin light scattering (BLS) spectrometer. Fig. 1a illustrates the magnetization of Pt(4 nm)/Co(1 nm)/Gd(2 nm) films. Due to the AFM coupling between Co and Gd layers, the total magnetization decreases with decreasing temperature. The compensation temperature, where the total magnetization exhibits a minimum value, is around 50K. As the temperature further decreases, the total magnetization starts to increase as the magnetization of Gd increases more rapidly compared to that of Co. Fig. 1b shows the temperature dependence of interfacial DMI in the Pt(4 nm)/Co(1 nm)/Gd(2 nm) film. It is clear that the interfacial DMI intensity initially increases with decreasing temperature, peaking at around 45K with a maximum value of approximately 3.21 mJ/m2. We further clarify that this behavior is strongly related to the temperature-driven perpendicular anisotropy in this system by anomalous Hall effect (AHE) measurements. Moreover, our results can qualitatively explain the observed most stable skyrmions in Co/Gd/Pt multilayers at the low temperature of 70K[1].References: [1] X. Wang et al., Phys. Rev. Mater. 6, 084412 (2022).