2Dimensional van der Waals Spin-Orbit Torque Technology

• Applicants: Professor Dr. Christian Back; Professor Dr. Jaroslav Fabian
• Subject Area: Theoretical Condensed Matter Physics
• Term: since 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 471797209

Engineering two-dimensional (2D) material van der Waals heterostructures by combining the best of different functional constituents can offer a plethora of opportunities in nanoelectronics. Here, we propose to develop all-2D spintronics platforms for the next generation of information technology based on 2D magnetic and topological spin-orbit materials. These hybrid systems can provide a strong synergy between spintronics and 2D materials, with the goal of combining “the best of both worlds”. Such integration of spin-orbit physics and magnetism in 2D heterostructures will enable groundbreaking functionalities in all-2D spin-orbit torque (SOT) technologies for low-power and non-volatile memory and logic devices.We will exploit low crystal symmetry of layered spin-orbit materials (SOM), hosting novel spin textures for the realization of efficient charge-to-spin conversion (CSC) with a significant out-of-plane spin-orbit field contribution for SOT technologies. We will start with basic investigation of CSC by using potentiometric methods in non-local spin valve geometry with graphene heterostructures. These studies will provide information about the main driving mechanisms of the CSC phenomena, such as the spin Hall, Rashba-Edelstein, or other spin-momentum locking effects to generate a giant and tunable spin polarization. Magnetic 2D crystals, on the other hand, exhibit a wide range of magnetic ordering and, extraordinarily, have the potential to be controlled by purely electronic means. Here, we will investigate 2D magnets for SOT technologies exploiting their low-dimensionality, perpendicular magnetic anisotropy, and the possibility of electric field control. We will examine the dynamics of magnetic excitations, their anisotropies, and controllability by gates, the critical parameters influencing the magnetic switching speed.This project will integrate 2D magnets and SOMs with engineered interfaces to establish exceptionally efficient SOT switching functionalities in all-2D materials platforms. We aim to study the fundamentals of magnetization dynamics and SOT switching behavior of hybrid structures using electronic, magnetotransport, time and spatially resolved magneto-optics, ferromagnetic resonance and 2nd harmonic measurements. The potential of the novel functionalities in these heterostructures will arise from the interplay of exotic spin textures, magnetic phases, proximity-induced exchange and spin-orbit effects at the interfaces of the 2D materials.

• DFG Programme: Research Grants
• International Connection: Sweden
• Cooperation Partner: Professor Dr. Saroj Dash