The project
The semiconductor industry heavily relies on materials whose extraction, production, and purification processes are currently unsustainable. Simultaneously, the escalating demand for data storage and transfer between electronic devices (from data centers to personal computers, mobile phones to Internet of Things devices, etc.) necessitates denser and faster technology.
In this context, nanoscale magnetism presents unique opportunities to revolutionize existing electronics.
By harnessing the electron’s spin and orbital properties, we can manipulate the magnetization of the system and enhance the magnetization switching efficiency. This is achieved through the amplification of torques exerted by current flowing through an adjacent non-magnetic metal. Building upon this mechanism, a novel storage device called Spin-Orbit Torque Magnetic Random Access Memory (SOT-MRAM) has been proposed and developed by several companies. SOT-MRAM demonstrates reduced power consumption and improved processing speed. However, these technologies still rely on the use of critical and potentially harmful materials such as heavy metals and rare earths, which are unsustainable for environmental and geopolitical reasons.
GREEN-MEM aims to boost the magnetization switching processes by leveraging materials with minimal environmental impact, and abundant on Earth, engineered in suitable multilayer configurations.
We will focus on light transition metals exhibiting diverse structural properties (such as textured versus single crystalline), distinct surface and interface characteristics (including surface potential, spin/orbital absorption/reflection), and varying electronic and magnetic phases (metal/insulator, ferromagnetic/antiferromagnetic orders).
By carefully designing the multilayer structures, we will exploit novel physical phenomena occurring at interfaces such as spin and orbital Hall effects, electron affinity between different materials and crystal and shape anisotropies. This allows to magnify magnetic torque (field- and antidamping-like) and spin-charge conversion, enabling efficient magnetization vector switching in in-plane and out-of-plane magnetized systems in SOT-MRAM-like geometry.
To understand the fundamental aspects responsible for these switching mechanisms, we will employ advanced experimental tools at short time and spatial scales, and with elemental resolution. Additionally, we will fabricate nano-devices with intentionally designed shapes to fine-tune the torque’s efficiencies.