I present our recent work on two-dimensional (2D) transition metal dichalcogenides (TMDs) doped with transition-metal atoms, targeting applications in spintronic memory and biosensing. First, I discuss the synthesis, doping, and ferromagnetism in Fe-doped monolayer TMDs, with a focus on spin-orbit torque (SOT) switching. Materials such as those containing heavy metals with strong spin-orbit coupling and topological insulators with spin-momentum locking generate substantial spin currents when subjected to electrical fields. When paired with van der Waals (vdW) magnets, these materials enhance spin-torque transfer efficiency, with the strong perpendicular magnetic anisotropy proving particularly useful for spintronic applications. Thinner vdW magnets are found to improve energy efficiency by enabling closer interaction between the magnetic layers and spin-accumulated interfaces. In our prior work (Nature Communications, 11, 2034, 2020), we introduced Fe-doped monolayer MoS₂, which is a 2D dilute magnetic semiconductor (DMS) that operates above room temperature, offering a promising solution for practical SOT applications. Building on this, I present our recent demonstration of highly energy-efficient, field-free, deterministic, and non-volatile SOT switching in Fe-doped monolayer MoS₂ deposited on a platinum Hall bar structure. The use of 2D DMS monolayers represents the first demonstration of SOT switching at the true atomic monolayer limit. Additionally, I briefly highlight our work on MoS₂-based sensors designed to enhance the precision of infectious disease diagnoses, ultimately leading to the development of effective and accessible diagnostic tools.

Biography:

Dr. E. H. Yang is a Professor of the Mechanical Engineering Department at Stevens Institute of Technology. He worked as a Senior Member of the Engineering Staff at NASA's Jet Propulsion Laboratory. Dr. Yang led several projects funded by NASA, DARPA, and NRO before joining Stevens in 2006. He secured over forty federal grants and contracts, including funding from the NSF, AFOSR, and the US Army. Among other honors, he was awarded the Lew Allen Award for Excellence at NASA/JPL in 2003, the Award for Research Excellence at Stevens in 2019 and the IEEE Technical Achievement Award (Advanced Career) from the IEEE Sensors Council in 2020. He is a Distinguished Lecturer of the IEEE Nanotechnology Council as well as the Sensors Council. Dr. Yang is Editor-in-Chief of the IEEE Sensors Reviews and  Chair of the IEEE Nanotechnology Council North Jersey Chapter. Dr. Yang is a Fellow of the National Academy of Inventors. In 2023, he was awarded the Master of Engineering, Honoris Causa, from Stevens Institute of Technology.