Tunable damping-like and field-like spin-orbit-torque in Pt/Co/HfO2 films via interfacial charge transfer

Abstract

The spin–orbit-torque (SOT) consists of dampinglike torque (DLT) and fieldlike torque (FLT), where the combined effects of these two torques need further consideration for efficient SOT switching. Here, the tunable correlation between the DLT and FLT is investigated in Pt/Co/HfO2 multilayers with different annealing temperatures (Ta). With increasing Ta, the FLT decreases monotonously, while both the sign and the magnitude of DLT are changed. Interfacial analysis results reveal that the tunable correlation of them is strongly dependent on the interfacial electron structure between the Co and HfO2 layer. The interfacial charge transfer between the Co, O, and Hf atoms could modify interfacial spin–orbit coupling and the crystal electric field (ECEF), which promotes the interface-generated SOT. This work demonstrates an effective method to tune the correlation of the two SOT components, a desirable feature which will be beneficial for the design of SOT-based devices.

Multiple modes of perpendicular magnetization switching scheme in single spin–orbit torque device

“…[20][21][22] Moreover, a number of researches have demonstrated that both the strength and sign of λ FL /λ DL can be adjusted by tuning the material types or fabrication processes. [20,23,24] The strength of field-like torque is related to multiple factors such as layer thickness, material system, interfacial intermixing, etc. This is a complicated issue and still under exploration.…”

Wedge-shaped HfO2 buffer layer-induced field-free spin-orbit torque switching of HfO2/Pt/Co structure

“…The HfO 2 , a promising high-K and ferroelectric material, [22] has been shown to change the interfacial electron structure and enhance interface SOT when used as a capping layer. [23] Exploring the influence of HfO 2 as a buffer layer on SOT is a critical area of research, however, it remains lacking.…”

Enhanced magneto-optical Kerr effect via the synergistic effect of surface plasmon resonance and spin–orbit coupling in Au@Pt nanohybrid layers

“…However, in previous studies, the heavy metals that have a role in the spin-orbit couplings are mostly composed of layered films, and the process of creating the micro-/nanostructures is expensive and time-consuming [25,26]. In this paper, construction of a type of Au@Pt NHs is provided by combining platinum with a high spin-orbit coupling effect into gold nanoparticles (AuNPs) with a surface plasmon effect.…”