Ab-initio study of magneto-ionic mechanisms in ferromagnet/oxide multilayers

Abstract

The application of gate voltages in heavy metal/ferromagnet/Oxide multilayer stacks has been identified as one possible candidate to manipulate their anisotropy at will. However, this method has proven to show a wide variety of behaviours in terms of reversibility, depending on the nature of the metal/oxide interface and its degree of oxidation. In order to shed light on the microscopic mechanism governing the complex magneto-ionic behaviour in $\text{Ta/CoFeB/}{\text{HfO}}_2$, we perform ab-initio simulations on various setups comprising ${\text{Fe/O, Fe/HfO}}_2$ interfaces with different oxygen atom interfacial geometries. After the determination of the more stable interfacial configurations, we calculate the magnetic anisotropy energy on the different unit cell configurations and formulate a possible mechanism that well describes the recent experimental observations in $\text{Ta/CoFeB/}{\text{HfO}}_2$.

8 pages, 5 figures

References in corpus (4)

• Magneto-ionic Control of Interfacial Magnetism
• Large and robust electrical spin injection into GaAs at zero magnetic field using an ultrathin CoFeB/MgO injector
• Comparison of first-principles methods to extract magnetic parameters in ultra-thin films: Co/Pt(111)
• Perpendicular magnetic anisotropy and Dzyaloshinskii-Moriya interaction at an oxide/ferromagnetic metal interface