Efficient Control of Magnetization Dynamics Via W/CuO${}_{\text{x}}$ Interface

Abstract

Magnetization dynamics, which determine the speed of magnetization switching and spin information propagation, play a central role in modern spintronics. Gaining its control will satisfy the different needs of various spintronic devices. In this work, we demonstrate that the surface oxidized Cu (CuO${}_{\text{x}}$) can be employed for the tunability of magnetization dynamics of ferromagnet (FM)/heavy metal (HM) bilayer system. The capping CuO${}_{\text{x}}$ layer in CoFeB/W/CuO${}_{\text{x}}$ trilayer reduces the magnetic damping value in comparison with the CoFeB/W bilayer. The magnetic damping even becomes lower than that of the CoFeB/CuO${}_{\text{x}}$ by ~ 16% inferring the stabilization of anti-damping phenomena. Further, the reduction in damping is accompanied by a very small reduction in the spin pumping-induced output DC voltage in the CoFeB/W/CuO${}_{\text{x}}$ trilayer. The simultaneous observation of anti-damping and spin-to-charge conversion can be attributed to the orbital Rashba effect observed at the HM/CuO${}_{\text{x}}$ interface. Our experimental findings illustrate that the cost-effective CuO${}_{\text{x}}$ can be employed as an integral part of modern spintronics devices owing to its rich underneath spin-orbital physics.