Highly efficient spin-orbit torque switching of perpendicular magnetization using topological insulators with a high thermal stability*

Recent advances in using topological insulators (TIs) with ferromagnets (FMs) at room temperature have opened up an innovative avenue in spin-orbit torque non-volatile magnetic memory and low dissipation electronics applications. However, a major challenge of direct integration of TIs with a perpendicularly magnetized FM remains in retaining an extraordinary charge-to-spin conversion efficiency in TIs. In addition, the indispensable thermal compatibility with modern CMOS technologies has not yet been achieved in TI-based structures. In this talk, we will demonstrate the high-quality integration of perpendicularly magnetized FM with TI through a light metal insertion layer and achieved efficient magnetization switching at ambient temperature. The energy efficiency of TIs is at least an order magnitude larger than those typical values of heavy metals (e.g., Ta, Pt, etc.). Moreover, we demonstrate that the current-induced magnetization switching and perpendicular magnetic anisotropy of the integrated FM can be well preserved for an annealing temperature up to 400C. The compatibility of our TI-based thin films with the modern CMOS back-end-of-line process paves the way towards TI-based low-dissipation spintronic applications.