Tunable unconventional spin orbit torque magnetization dynamics in van der Waals heterostructures
Lalit Pandey, Bing Zhao, Karma Tenzin, Roselle Ngaloy, Veronika Lamparská, Himanshu Bangar, Aya Ali, Mahmoud Abdel-Hafiez, Gaojie Zhang, Hao Wu, Haixin Chang, Lars Sjöström, P. K. Rout, Jagoda Sławińska, Saroj P. Dash
Abstract
Abstract Two-dimensional quantum material heterostructures can offer a promising platform for energy-efficient non-volatile spin-based technologies. However, spin dynamics experiments to understand the basic spin-orbit torque phenomena are so far lacking. Here, we demonstrate unconventional out-of-plane magnetization dynamics, and energy-efficient and field-free spin-orbit torque switching in a van der Waals heterostructure comprising out-of-plane magnet Fe 3 GaTe 2 and topological Weyl semimetal TaIrTe 4 . We measured non-linear second harmonic Hall signal in TaIrTe 4 /Fe 3 GaTe 2 devices to evaluate the magnetization dynamics, which is characterized by large and tunable out-of-plane damping-like torque. Energy-efficient and deterministic field-free SOT magnetization switching is achieved at room temperature with a very low current density. First-principles calculations unveil the origin of the unconventional charge-spin conversion phenomena, considering the crystal symmetry and electronic structure of TaIrTe 4 . These results establish that van der Waals heterostructures provide a promising route to energy-efficient, field-free, and tunable spintronic devices.