Model-Guided Development of Spin-Dependent-Tunnel Junctions for Magnetoelectronic Devices

This Small Business Technology Transfer Phase II Program will demonstrate a magnetic field sensor device of high sensitivity using spin-dependent tunnel (SDT) materials. The tunnel materials will be developed with guidance from the state of the art realistic atomistic modeling and aided by state of the art nanostructural characterization techniques of 3-D atom probe and high-resolution transmission electron microscopy. Due to the unique requirements of the thin tunnel barrier (~1nm) and its interfaces with two ferromagnetic layers, experimental approach itself is inefficient in developing new junctions. There is a critical need for realistic modeling in guiding junction fabrication, and this project is specifically designed for the purpose. A robust realistic atomistic model has been established and a record high TMR value has been achieved experimentally in the Phase I. In Phase II the model will be perfected and extensive simulation and experiments will be conducted to optimize the tunnel junctions. With NVE''''''''s experience in experimentally developing SDT devices, UVA''''''''s expertise in realistic atomistic simulation and nanostructural characterization, and U of Oxford''''''''s renowned 3-D atomic probe imaging, as well as our past collaborations among the team members, the model-guided approach has a high potential for success.